| Mammillaria acanthophlegma Lehm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria acanthostephes Lehm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria acicularis Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria aciculata Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria aciculatus Otto ex Pfeiff. | 
		Unresolved | 
		  | 
		TRO | 
	
	
		| Mammillaria acifer Jacobi | 
		Unresolved | 
		  | 
		TRO | 
	
	
		| Mammillaria actinoplea Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria acultzingensis T. Linzen et al. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria adunca Scheidw. ex C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria aeruginosus Scheidw. | 
		Unresolved | 
		  | 
		TRO | 
	
	
		| Mammillaria affinis DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria aggregata Engelm. ex S. Watson | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria alamensis R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria albata Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria albescens Tiegel | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria albiarmata Boed. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria albicans (Britton & Rose) A. Berger | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria albicans subsp. albicans  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria albicans subsp. fraileana (Britton & Rose) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria albicans f. fraileana (Britton & Rose) Lüthy | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria albicoma Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria albida Haage ex Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria albidula Backeb. ex Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria albiflora Backeb. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria albilanata Backeb. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria albilanata subsp. oaxacana D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria albilanata subsp. reppenhagenii (D.R. Hunt) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria albilanata subsp. tegelbergiana (H.E. Gates ex G.E. Linds.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria albiseta C.F.Först. & Rümpler | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria albrechtiana Wohlschl. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria aloides Monv. ex Labour. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria alpina Mart. ex Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria alversonii (J.M. Coult.) Zeiss. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria amabilis Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria amajacensis Brachet & M. Lacoste | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria ambigua G.Don ex Loudon | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria amoena Hoppfer ex Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria anancistria Lem. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria ancistracantha Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria ancistrata Scheidw. ex Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria ancistria Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria ancistroides Lehm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria andreae Pfeiff. ex Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria andreae J.A.Purpus & Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria angelensis R.T. Craig bis | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria angelensis var. estebanensis (G.E. Linds.) Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria anguinea Otto ex Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria angularis G.K. Link & Otto | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria anisacantha Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria anniana Glass & R.C. Foster | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria antesbergeriana A.B. Lau | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria apamensis Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria apozolensis Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria applanata Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria areolosa (Lem.) Hemsl. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria argentea Fennel in Otto & A. Dietr. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria arida Rose ex Quehl | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria arietina Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria arizonica Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria arizonica var. alversonii (J.M. Coult.) Davidson & Moxley | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria armatissima R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria armillata K. Brandegee | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria armillata subsp. cerralboa (Britton & Rose) D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria arroyensis Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria ascensionis Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria ascensionis var. nominis-dulcis (A.B. Lau) Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria aselliformis (Ehrenb.) H.P.Kelsey & Dayton | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria asterias Cels ex Salm-Dyck, L. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria atrata Hook. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria atroflorens Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria atrorubra Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria atrosanguinea Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria aulacantha DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria aulacothele Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria aurata Pfeiff. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria aurea C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria aureiceps Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria aureilanata Backeb. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria aureispina (A.B.Lau) Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria aureoviridis Heinrich | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria auriareolis Tiegel | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria auricantha  | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria auricoma A. Dietr. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria aurihamata Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria aurisaeta Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria auritricha R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria aurorea A.Dietr. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria autumnalis A.Dietr. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria avila-camachoi Shurly | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria aylostera Werderm. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria bachmannii Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria backebergiana F.G. Buchenau | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria backebergiana subsp. backebergiana  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria backebergiana subsp. ernestii (Fittkau) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria backebergiana var. ernestii (Fittkau) Glass & R.A. Foster | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria badispina C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria balsasensis Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria balsasoides R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria bambusiphila Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria barbata Engelm. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria barbata var. garessii (Cowper) J. Lode | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria barbata var. morricalii (Cowper) J. Lode | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria barbata var. santaclarensis (Cowper) J. Lode | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria barkeri Shurly | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria barlowii Regel & Klein | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria baumii Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria baxteriana (H.E. Gates) Boed. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria beiselii Diers | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria bella Backeb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria bellacantha R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria bellatula Foerster | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria bellisiana R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria beneckei Ehrenb. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria beneckei var. multiceps Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria bergenii Ehrenb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria bergii Miq. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria berkiana A.B. Lau | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria bernalensis Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria bicolor Lehm. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria bicolor var. nobilis (Pfeiff.) C.F. Först. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria bifurca A.Dietr. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria biglandulosa Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria bihamata Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria binops J.N.Haage ex C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria blossfeldiana Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria blossfeldiana var. shurliana Wiggins | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria bocasana Poselger | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria bocasana subsp. eschauzieri (J.M. Coult.) Fitz Maurice & B. Fitz Maurice | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria bocensis Craig | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria bockii Foerster | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria boedekeriana Quehl | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria boelderliana Wohlschl. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria bogotensis Werderm. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria bombycina Quehl | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria bombycina subsp. perezdelarosae (Bravo & Scheinvar) D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria bonavitii Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria bonavitii Schmoll ex Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria boolii G.E. Linds. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria borwigii J.A.Purpus | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria brachytrichion Lüthy | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria brandegeei (J.M. Coult.) K. Brandegee | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria brandegeei subsp. gabbii (Engelm. ex J.M. Coult.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria brandegeei subsp. glareosa (Boed.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria brandegeei subsp. lewisiana (H.E. Gates) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria brandegei var. gabbii (Engelm. ex J.M. Coult.) R.T. Craig bis | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria brauneana Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria bravoae R.T. Craig | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria brevicrinita Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria brevimamma Zucc. ex Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria breviseta Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria brevispina Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria brongniartii Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria brownii Toumey | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria bucareliensis R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria buchenaui Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria buchheimiana Quehl | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria bullardiana (H.E.Gates) Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria bumamma Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria busonii Bachel | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria bussleri Mundt ex Schum. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria buxbaumeriana Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria cadereytensis R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria caerulea R.T. Craig bis | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria caesia Ehrenb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria caespitia DC. | 
		Unresolved | 
		  | 
		TRO | 
	
	
		| Mammillaria caespititia DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria caespitosa (Engelm.) A.Gray | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria caespitosa Pfeiff. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria calacantha Tiegel | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria calcarata Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria calleana Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria calochlora auct. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria camptotricha Dams | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria candida Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria candida var. caespitosa Voss | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria candida var. estanzuelensis Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria candida subsp. ortiz-rubiana (Bravo) Krainz | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria candida var. ortiz-rubiana (Bravo) B.Hofm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria candida var. rosea Salm-Dyck ex K. Schum. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria canelensis R.T. Craig | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria canescens Jacobi | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria canescens Pfeiff. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria capensis (H.E. Gates) Craig | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria caput-medusae Otto | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria caracassana Otto ex Salm-Dyck | 
		Synonym | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria carmenae Castañeda | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria carnea Zucc. ex Pfeiff. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria carretii Rebut ex K. Schum. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria casoi Bravo | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria castaneoides Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria castaneoides Lem. ex Labour. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria catafracta Mart. ex Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria cataphracta Mart. ex Pfeiff. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria caudata G.Don ex Loudon | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria celeriana  | 
		Unresolved | 
		  | 
		TRO | 
	
	
		| Mammillaria celsiana Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria celsiana var. guatemalensis Eichlam | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria centralifera Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria centraliplumosa Fittkau | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria centraliplumosa var. gracilis Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria centricirrha Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria centrispina Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria cephalophora Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria ceratites Quehl | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria ceratocentra Bergman | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria ceratophora Lehm. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria cerralboa (Britton & Rose) Orcutt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria chaffeyi (Britton & Rose) Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria chapinensis Eichlam & Quehl | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria chavezei Cowper | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria chiapensis Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria chica Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria chionocephala J.A. Purpus | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria chlorantha Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria chrysacantha Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria circumtexta Mart. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria cirrhifera Mart. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria cirrosa Poselg. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria clava Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria clavata Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria claviformis Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria coahuilensis (Boed.) Moran | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria coahuilensis subsp. albiarmata (Boed.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria coahuilensis var. albiarmata (Boed.) Hofmann | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria coahuilensis subsp. coahuilensis  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria coccinea G.Don | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria collina J.A. Purpus | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria collinsii (Britton & Rose) Orcutt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria colonensis R.T. Craig bis | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria columbiana Salm-Dyck | 
		Accepted | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria columbiana subsp. yucatanensis (Britton & Rose) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria columnaris Mart. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria columnaroides Lawr. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria compacta Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria compacticaulis Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria compressa DC. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria compressa subsp. centralifera (Repp.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria compressa subsp. compressa  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria confinis J.N.Haage ex Walp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria confinis K.Schum. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria confusa  | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria conica Haw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria coniflora Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria conimamma Linke | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria conoidea DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria conopsea Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria conspicua J.A. Purpus | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria conspicua var. vaupelii (Tiegel) Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria contacta H.L.Wendl. ex C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria convoluta St.-Lag. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria conzattii Orcutt | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria corbula Herrera | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria cordigera Heese | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria corioides Bosch ex Sweet | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria cornifera DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria cornifera var. implexicoma (Lem.) Salm-Dyck | 
		Unresolved | 
		  | 
		TRO | 
	
	
		| Mammillaria cornuta Hildm. ex Schum. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria corollaria Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria coronaria Haw. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria coronata Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria coryphides Forbes ex C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria cowperae Shurly | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria craigii G.E. Linds. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria crassa Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria crassimammillis Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria crassior Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria crassispina Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria crebrispina DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria crebrispina var. nitida (Scheidw.) Labour. | 
		Unresolved | 
		  | 
		TRO | 
	
	
		| Mammillaria criniformis DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria crinigera Otto ex C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria crinita DC. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria crinita subsp. crinita  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria crinita subsp. leucantha (Boed.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria crinita subsp. painteri (Rose) U. Guzmán | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria crinita subsp. scheinvariana (R. Ortega & Glass in Glass) Fitz Maurice & B. Fitz Maurice | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria crinita subsp. wildii (A. Dietr.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria crispiseta R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria crocidata Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria crucigera Mart. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria crucigera subsp. tlalocii (Repp.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria cuneiflora Hitchen ex J.Forbes | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria curvata Pfeiff. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria curvispina Otto | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria cylindracea DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria dactylothele Labour. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria daedalea Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria daimonoceras Lem. ex Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria dasyacantha Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria dawsonii (Houghton) R.T. Craig bis | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria dealbata A. Dietr. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria decipiens Scheidw. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria decipiens subsp. albescens (Tiegel) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria decipiens subsp. camptotricha (Dams) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria declivis A.Dietr. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria decora C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria deficiens Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria deficum C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria deflexispina Lem. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria deherdtiana Farwig | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria deherdtiana subsp. dodsonii (Bravo) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria delaetiana Quehl | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria densa Link & Otto | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria densispina (J.M. Coult.) Orcutt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria denudata (Engelm.) A.Berger | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria depressa Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria deserti Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria diacantha Lem. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria diacantha J.N.Haage ex Steud. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria diacentra Jacobi | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria diadema Muehlenpf. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria diaphanacantha Lem. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria dichotoma Sweet | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria dietrichii Tiegel | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria difficilis Quehl | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria digitalis Ehrenb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria diguetii (F.A.C.Weber) D.R.Hunt | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria dioica K. Brandegee | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria dioica subsp. angelensis (R.T. Craig bis) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria dioica subsp. dioica  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria dioica subsp. estebanensis (G.E. Linds.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria dioica var. incerta (Parish) Munz | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria dioica var. insularis K. Brandegee | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria dioica f. phitauiana (E.M. Baxter) Neutel. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria dioica f. verhaertiana (Boed.) Neutel. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria disciformis DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria discolor Haw. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria discolor var. aciculata (Otto ex Pfeiff.) Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria discolor var. albida (Haage ex Pfeiff.) Salm-Dyck | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria discolor var. curvispina (Otto) Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria discolor subsp. discolor  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria discolor subsp. esperanzaensis (Boed.) D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria discolor var. nitens (Otto ex Linke) Salm-Dyck | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria discolor subsp. ochoterenae (Bravo) U. Guzmán | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria discolor var. ochoterenae (Bravo) Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria discolor subsp. schmollii (Bravo) Linzen | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria discolor var. schmollii (Bravo) Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria divaricata Dieter. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria divergens DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria dixanthocentron Backeb. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria dixanthocentron subsp. dixanthocentron  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria dixanthocentron subsp. flavicentra (Backeb.) U. Guzmán | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria dixanthocentron var. flavicentra (Backeb.) Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria dixanthocentron var. rubrispina R. Wolf | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria dodsonii Bravo | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria dolichacantha Lem. ex C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria dolichocentra Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria donatii Berge ex K. Schum. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria droegeana (K.Schum.) Borg | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria dumetorum J.A. Purpus | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria duoformis R.T. Craig & E.Y. Dawson | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria durangensis Runge ex K. Schum. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria durangicola Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria durispina Boed. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria duwei Rogoz. & Appenz. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria dyckiana Zucc. ex Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria ebenacantha Shurly | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria eborina Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria eburnea Miq. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria echinaria DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria echinata DC. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria echinocactoides Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria echinoidea Quehl | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria echinoides Quehl | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria echinops Scheidw. ex C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria echinus Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria egregia Backeb. ex Rogoz. & Appenz. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria ehrenbergii Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria eichlamii Quehl | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria ekmanii Werderm. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria elegans DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria elegans var. meissneri (Ehrenb.) Hofmann | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria elegans var. schmollii R.T. Craig bis | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria elephantidens Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria elongata (Salm-Dyck) Hemsl. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria elongata DC. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria elongata subsp. echinaria (DC.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria elongata subsp. elongata  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria emskoetteriana Quehl | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria emundtsiana C.F.Först. & Rümpler | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria engelmannii Cory | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria enneacantha Otto ex C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria erecta Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria erectacantha Foerster | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria erectohamata Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria eriacantha Link & Otto ex Pfeiff. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria eriantha Pfeiff. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria erinacea H. Wendl. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria ernestii Fittkau | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria erythra Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria erythrocalix Buchenau | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria erythrosperma Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria eschanzieri (Coult.) R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria eschauzieri (J.M. Coult.) R.T. Craig | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria eschauzieri (J.M. Coult.) R.T. Craig bis | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria escobaria Cory | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria esperanzaensis Boed. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria esseriana Boed. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria estanzuelensis H. Möller ex A. Berger | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria estebanensis G.E. Linds. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria euacantha Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria euchlora Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria eugenia Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria evanescens C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria evermanniana (Britton & Rose) Orcutt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria eximia Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria exsudans Zucc. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria falcata C.F.Först. & Rümpler | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria falsicrucigera Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria farinosa Fennel | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria fasciculata Engelm. ex S. Watson | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria felicis Schreier ex W. Haage | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria felipensis Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria fellneri Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria fennelii Hopffer | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria fera-rubra Schmoll ex R.T. Craig | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria fertilis Hildm. ex K. Schum. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria fischeri Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria fissurata Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria fittkaui Glass & R.C. Foster | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria fittkaui subsp. limonensis (Repp.) Lüthy | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria flava Otto & A.Dietr. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria flavescens (DC.) DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria flavescens (DC.) Pfeiff. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria flavescens var. nivosa (Link ex Pfeiff.) Backeb. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria flavicentra Backeb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria flaviceps Scheidw. ex Labour. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria flavicoma C.F.Först. & Rümpler | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria flavihamata Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria flavovirens Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria floccigera Otto ex Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria floresii Fritz Schwarz | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria floribunda Hook | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria fobeana Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria foersteri Muehlenpf. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria fordii Orcutt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria formosa Galeotti ex Scheidw. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria formosa subsp. chionocephala (J.A. Purpus) D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria formosa subsp. microthele (Muehlenpf.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria formosa subsp. pseudocrucigera (R.T. Craig) D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria fortispina Shurly | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria foveolata Muehlenpf. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria fragilis Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria fraileana (Britton & Rose) Boed. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria freudenbergeri Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria freudenbergii Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria fuauxiana Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria fuliginosa Salm-Dyck | 
		Synonym | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria fulvispina Haw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria funckii Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria furfuracea Watson | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria fuscata Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria fuscohamata Backeb. ex Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria gabbii Engelm. ex J.M. Coult. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria × gajii Chvastek & Halda | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria galeottii Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria garessii Cowper | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria gasseriana Boed. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria gasterantha Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria gatesii M.E. Jones | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria gaumeri (Britton & Rose) Orcutt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria geberweileriana Haage | 
		Unresolved | 
		  | 
		TRO | 
	
	
		| Mammillaria gebweileriana J.N.Haage ex C.F.Först. & Rümpler | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria geminata Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria geminispina Haw. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria geminispina subsp. geminispina  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria geminispina subsp. leucocentra (O. Berg) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria gibbosa Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria gigantea Hildm. ex K. Schum. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria gigantothele C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria giselae Mart.-Aval. & Glass | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria glabrata Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria gladiata Mart. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria gladiispina Boed. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria glanduligera Otto & A. Dietr. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria glareosa Boed. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria glassii R.A. Foster | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria glassii subsp. ascensionis (Repp.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria glassii var. ascensionis (Repp.) Glass & R.A. Foster | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria glassii subsp. nominis-dulcis (A.B. Lau) U. Guzmán | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria glassii var. nominis-dulcis A.B. Lau | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria glassii subsp. siberiensis (A.B. Lau) U. Guzmán | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria glassii var. siberiensis A.B. Lau | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria glauca A. Dietr. ex Linke | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria globosa Linke | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria glochidiata Mart. | 
		Accepted | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria glomerata DC. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria goldii Glass & R.A. Foster | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria golziana Haage | 
		Unresolved | 
		  | 
		TRO | 
	
	
		| Mammillaria goodrichii Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria goodrichii var. rectispina E.Y. Dawson | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria goodridgii Scheer | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria goodridgii var. rectispina Dawson | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria gracilis Pfeiff. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria gracilis var. pulchella Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria graessneriana Boed. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria grahamii Engelm. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria grahamii var. oliviae (Orcutt) L.D. Benson | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria grandicornis Muehlenpf. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria grandiflora Otto ex Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria grandis Hitchen ex J.Forbes | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria granulata Meinsh. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria greggii (Engelm.) Saff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria grisea Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria grusonii Runge | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria guanajuatensis Rudge ex K.Schum. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria gueldemanniana Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria guelzowiana Werderm. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria guerkeana Boed. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria guerreronis (Bravo) Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria guiengolensis Bravo & T.MacDoug. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria guillauminiana Backeb. | 
		Accepted | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria guilleminiana Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria guirocobensis R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria gummifera Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria gummifera var. applanata (Engelm.) L.D. Benson | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria gummifera var. hemisphaerica (Engelm.) L.D. Benson | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria gummifera var. macdougalii (Rose) L.D. Benson | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria gummifera var. meiacantha (Engelm.) L.D. Benson | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria haageana Pfeiff. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria haageana subsp. acultzingensis (T. Linzen et al.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria haageana var. collina (J.A. Purpus) T. Linzen et al | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria haageana subsp. conspicua (J.A. Purpus) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria haageana subsp. elegans D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria haageana subsp. haageana  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria haageana subsp. meissneri (Ehrenb.) U. Guzmán | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria haageana subsp. san-angelensis (Sánchez-Mej.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria haageana subsp. schmollii (Werderm.) D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria haageana var. schmollii (R.T. Craig bis) D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria haageana subsp. vaupelii (Tiegel) U. Guzmán | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria haasii J. Meyrán | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria haehneliana Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria haematactina Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria hahniana Werderm. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria hahniana subsp. bravoae (R.T. Craig) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria hahniana subsp. mendeliana (Bravo) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria hahniana subsp. woodsii (R.T. Craig) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria halbingeri Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria halei Brandegee | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria halhingeri Boed. | 
		Unresolved | 
		  | 
		TRO | 
	
	
		| Mammillaria hamata Lehm. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria hamiltonhoytiae (Bravo) Werderm. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria hamuligera Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria haselaffii Ehrenb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria hasseloffii Ehrenb. ex Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria hastifera Krainz & A.Keller | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria haudeana A.B. Lau & K. Wagner | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria haynii Ehrenb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria heeseana McDowell | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria heidiae Krainz | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria heinei Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria helicteres DC. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria hemisphaerica Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria hennisii Boed. | 
		Synonym | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria hepatica Ehrenb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria hernandezii Glass & R.C. Foster | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria herrerae Werderm. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria herrerae var. albiflora Werderm. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria herrmannii Ehrenb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria hertrichiana R.T. Craig | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria heteracantha Mart. ex Pfeiff. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria heteracentra Otto ex C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria heteromorpha Scheer | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria hexacantha Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria hexacentra Otto ex C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria heyderi Muehlenpf. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria heyderi var. applanata (Engelm.) Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria heyderi var. bullingtoniana Castetter, P. Pierce & K.H. Schwer. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria heyderi subsp. gaumeri (Britton & Rose) D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria heyderi subsp. gummifera (Engelm.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria heyderi subsp. hemisphaerica (Engelm.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria heyderi var. hemisphaerica Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria heyderi subsp. heyderi  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria heyderi subsp. macdougalii (Rose) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria heyderi var. macdougalii (Rose) L.D. Benson | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria heyderi subsp. meiacantha (Engelm.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria heyderi var. meiacantha (Engelm.) L.D. Benson | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria hidalgensis Purpus | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria hirschtiana F.Haage | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria hirsuta Boed. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria hirsuta var. grandis Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria hoffmannseggii Hoffmanns. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria hoolii Linds. | 
		Unresolved | 
		  | 
		TRO | 
	
	
		| Mammillaria hopferiana Linke | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria horripila Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria huajuapensis Bravo | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria hubertmulleri Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria huiguerensis Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria huitzilopochtli D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria huitzilopochtli var. niduliformis A.B. Lau | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria huitzilopochtli subsp. niduliformis (A.B. Lau) Pilbeam | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria humboldtii Ehrenb. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria humilior C.F.Först. ex K.Schum. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria hutchisoniana (H.E. Gates) Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria hutchisoniana var. bullardiana (H.E. Gates) Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria hutchisoniana subsp. hutchisoniana  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria hutchisoniana subsp. louisae (G.E. Linds.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria hyatricina Lawr. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria hybrida Pfeiff. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria hystrix Mart. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria icamolensis Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria ignota Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria igualensis Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria imbricata Wegener | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria implexicoma Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria inaiae Craig | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria incerta Parish | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria inclinis Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria inconspicua Scheidw. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria incurva Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria infernillensis R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria ingens Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria insularis H.E. Gates | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria intertexta DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria intricata Otto ex C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria irregularis DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria isabellina Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria isotensis Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria jalappensis Pfeiff. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria jaliscana (Britton & Rose) Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria jaliscana subsp. zacatecasensis (Shurly) D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria johnstonii (Britton & Rose) Orcutt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria joossensiana Quehl | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria jozef-bergeri Wojn. & Prajer | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria jucunda Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria karstenii Poselg. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria karwinskiana Mart. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria karwinskiana subsp. beiselii (Diers) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria karwinskiana subsp. collinsii (Britton & Rose) D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria karwinskiana subsp. karwinskiana  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria karwinskiana subsp. nejapensis (R.T. Craig & E.Y. Dawson) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria karwinskii Lawr. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria kelleriana Schmoll | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria kewensis Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria kleinii Regel | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria kleiniorum Appenz. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria kleinschmidtiana Zeiss. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria klissingiana Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria klugii Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria knebeliana Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria knipelliana Quehl | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria knippeliana Quehl | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria kraehenbuehlii (Krainz) Krainz | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria krameri Muehlenpf. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria krasuckae Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria krauseana K.Schum. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria kuentziana P.Fearn & B.Fearn | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria kunthii Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria kunzeana Boed. & Quehl | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria kupcakii Halda & Sladk. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria lactescens Meinsh. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria laeta Meinsh. ex C.F.Först. & Rümpler | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria lamprochaeta Jacobi | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria lanata Orcutt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria laneusumma R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria lanifera Haw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria lanigera Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria lasiacantha Engelm. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria lasiacantha var. denudata Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria lasiacantha subsp. egregia (Backeb. ex Rogoz. & Appenz.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria lasiacantha subsp. hyalina D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria lasiacantha subsp. lasiacantha  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria lasiacantha subsp. magallanii (Schmoll ex R.T. Craig) D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria lassonneriei Rebut ex K.Schum. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria latimamma DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria latispina (Haw.) Tate | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria laui D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria laui f. dasyacantha D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria laui subsp. dasyacantha (D.R. Hunt) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria laui f. subducta D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria laui subsp. subducta (D.R. Hunt) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria lehmannii Otto | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria leidiae Krainz | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria lengdobleriana Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria lenta K. Brandegee | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria leona Poselger | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria leptacantha (A.B.Lau) Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria lesaunieri Rebut ex K.Schum. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria leucacantha DC. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria leucantha Boed. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria leucocarpa Scheidw. ex Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria leucocentra O. Berg | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria leucocephala Pfeiff. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria leucocephala Schmoll ex Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria leucodasys Salm-Dyck ex Scheer | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria leucodictia Link | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria leucotricha Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria lewinii (Henn.) H.Karst. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria lewisiana H.E. Gates | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria limonensis Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria linaresensis R. Wolf & F. Wolf | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria lindheimeri Engelm. ex Hemsl. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria lindsayi R.T. Craig | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria lindsayi var. cobrensis Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria lindsayi var. rubriflora Hils. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria linkeana Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria littoralis K. Brandegee | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria livida Fennel in Otto & A. Dietr. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria lloydii (Britton & Rose) Orcutt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria longicoma (Britton & Rose) A. Berger | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria longiflora (Britton & Rose) A. Berger | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria longiflora subsp. longiflora  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria longiflora subsp. stampferi (Repp.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria longiflora f. stampferi (Repp.) D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria longihamata Engelm. | 
		Unresolved | 
		  | 
		TRO | 
	
	
		| Mammillaria longimamma DC. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria longimamma var. sphaerica (A. Dietr.) L.D. Benson | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria longiseta Muehlenpf. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria longispina Rchb. ex Terscheck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria loricata Mart. ex Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria louisae G.E. Linds. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria ludwigii Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria luethyi G.S. Hinton | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria lutescens J.Forbes | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria luthieniae Laferr. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria macdougalii Rose | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria macdowellii K.Schum. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria machucae W.A.Fitz Maur. & B.Fitz Maur. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria macracantha DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria macrantha Salm-Dyck ex C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria macromeris Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria macrothele Mart. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria maelenii Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria magallanii Schmoll ex R.T. Craig | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria magneticola J. Meyrán | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria magnifica F.G. Buchenau | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria magnimamma Haw. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria magnimamma var. arietina (Lem.) Salm-Dyck | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria mainiae K. Brandegee | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria maletiana Cels | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria mamillaria Scheeren | 
		Unresolved | 
		  | 
		TRO | 
	
	
		| Mammillaria mammillaris (L.) H.Karst. | 
		Accepted | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria manana W.A.Fitz Maur. & B.Fitz Maur. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria marcosii Fitz Maurice, B. Fitz Maurice & Glass | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria maritima (G.E. Linds.) D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria marksiana Krainz | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria marnieriana Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria marshalliana (H.E.Gates) Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria martiana Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria martinezii Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria maschalacantha Monv. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria mathildae Kraehenb. & Krainz | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria matudae Bravo | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria mayensis R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria mazatlanensis K. Schum. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria mazatlanensis subsp. mazatlanensis  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria mazatlanensis var. monocentra Craig | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria mazatlanensis subsp. patonii (Bravo) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria megacantha Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria meiacantha Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria meissneri Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria melaleuca Karw. ex Salm-Dyck | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria melanacantha C.F.Först. & Rümpler | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria melanocentra Poselger | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria melanocentra subsp. linaresensis (R. Wolf & F. Wolf) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria melanocentra subsp. melanocentra  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria melanocentra subsp. rubrograndis (Repp. & A.B. Lau) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria melilotiae Laferr. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria melispina Werderm. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria mendeliana (Bravo) Werderm. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria mercadensis Patoni | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria mercadensis var. guillauminiana (Backeb.) Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria meridiorosei Castetter, P. Pierce & K.H. Schwer. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria mexicensis R.T. Craig bis | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria meyranii Bravo | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria micans A. Dietr. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria micracantha Miq. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria micrantha C.F.Först. & Rümpler | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria microcarpa Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria microcarpa var. auricarpa W.T. Marshall | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria microcarpa subsp. grahamii (Engelm.) Mottram | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria microceras Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria microhelia Werderm. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria microheliopsis Werderm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria micromeris Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria micromeris var. greggii Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria micromeris var. unguispina Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria microthele Muehlenpf. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria miegiana W. Earle | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria mieheana Tiegel | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria milleri (Britton & Rose) Boed. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria milleri f. oliviae (Orcutt) Neutel. | 
		Unresolved | 
		  | 
		TRO | 
	
	
		| Mammillaria minima Rchb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria miqueliana Pfeiff. ex C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria mirabilis Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria missouriensis Sweet | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria missouriensis var. caespitosa (Engelm.) S. Watson | 
		Unresolved | 
		  | 
		TRO | 
	
	
		| Mammillaria missouriensis var. robustior (Engelm.) S. Watson | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria mitis Mill. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria mitlensis Bravo | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria moeller-valdeziana Appenz. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria moelleriana Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria mollendorffiana Shurly | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria mollihamata Shurly | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria monancistracantha Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria monancistria A.Berger ex K.Schum. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria monancistria Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria monocentra Jacobi | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria montensis R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria monticola Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria morganiana Tiegel | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria morricalii Cowper | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria movensis R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria mucronata Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria muehlenpfordtii Foerster | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria multicentralis R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria multiceps Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria multiceps var. elongata Meinsh. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria multiceps var. grisea Meinsh. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria multiceps var. humilis Meinsh. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria multiceps var. perpusilla Meinsh. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria multidigitata W.T. Marshall ex Linds. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria multiformis (Britton & Rose) Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria multihamata Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria multimamma F.M.Knuth | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria multiseta Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria mundtii K. Schum. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria mutabilis Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria mutica Salm-Dyck ex Hemsl. | 
		Unresolved | 
		  | 
		TRO | 
	
	
		| Mammillaria muultiradiata Mart. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria mystax Mart. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria nagliana Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria nana Backeb. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria napina J.A. Purpus | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria nazasensis (Glass & R.A.Foster) Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria neglecta Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria nejapensis R.T. Craig & E.Y. Dawson | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria nellieae (Croizat) Croizat | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria nelsonii (Britton & Rose) Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria neobertrandiana Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria neocoronaria F.M.Knuth | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria neocrucigera Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria neomexicana A. Nelson ex Coult. & A. Nelson | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria neomystax Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria neopalmeri R.T. Craig | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria neophaeacantha Fritz Schwarz | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria neopotosina R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria neoschwarzeana Fritz Schwarz | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria neumanniana Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria neumannii Regel ex C.F.Först. & Rümpler | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria nicholsonii auct. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria nickelsiae K. Brandegee | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria nigra Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria nigricans Fennel in Otto & A. Dietr. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria nitens Otto ex Linke | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria nitida Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria nivea H. Wendl. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria nivosa Link ex Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria nobilis Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria nolascana Radley | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria notesteinii Britton | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria noureddineana Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria nuda DC. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria nunezii (Britton & Rose) Orcutt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria nunezii subsp. bella (Backeb.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria nunezii subsp. nunezii  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria nuttallii Engelm. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria nuttallii var. caespitosa Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria nuttallii var. robustior (Engelm.) Engelm. & Bigelow | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria obconella Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria obliqua Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria obscura Hildm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria obvallata Otto | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria ocamponis Ochot. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria occidentalis Boed. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria ochoterenae (Bravo) Werderm. ex Backeb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria ocotillensis R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria octacantha DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria odehnalii Halda, Kupcák & Sladk. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria odieriana Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria oettingenii Zeiss. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria olivacea Pfeiff. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria oliviae Orcutt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria olorina Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria oothele Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria orcuttii Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria orestera L.D. Benson | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria ortegae (Britton & Rose) Orcutt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria ortiz-rubiana (Bravo) Werderm. ex Backeb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria oteroi Glass & R. Foster | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria ottonis Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria ovimamma Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pachycylindrica Backeb. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria pachyrhiza Backeb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pachytele Poselg. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pachythele Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pacifica (H.E.Gates) Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria painteri Rose | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pallescens Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria palmeri Jacobi | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria palmeri (J.M. Coult.) Jacobi | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria papasquiarensis (Bravo ex S.Arias Montes, U. Guzman Cruz & S. Gama Lopez) Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria papyracantha Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria parensis R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria parkinsonii Ehrenb. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria parmentieri Link & Otto | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria parrasensis Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria parvimamma Haw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria parvissima Karw. ex C.F.Först. & Rümpler | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria patonii (Bravo) Werderm. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria paulii Linzen | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pazzani Stieber | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria peacockii C.F.Först. & Rümpler | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pectinata Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pectinifera F.A.C. Weber | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria pectinifera f. solisioides (Backeb.) Sánchez-Mej. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria peninsularis (Britton & Rose) Orcutt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria pennispinosa Krainz | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria pennispinosa subsp. brachytrichion (Lüthy) U. Guzmán | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria pennispinosa var. nazasensis Glass & R. Foster | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pennispinosa subsp. nazasensis (Glass & R. Foster) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria pennispinosa subsp. pennispinosa  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria pentacantha Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria perbella Hildm. ex K. Schum. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria perezdelarosae Bravo & Scheinvar | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria perezdelarosae subsp. perezdelarosae  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria perote Pfeiff. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria perpusilla Meinsh. ex C.F.Först. & Rümpler | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria perringii Hildm. ex K.Schum. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria persicina Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pertinata Engelm. | 
		Unresolved | 
		  | 
		TRO | 
	
	
		| Mammillaria petrophila K. Brandegee | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria petrophila subsp. arida (Rose ex Quehl) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria petrophila subsp. baxteriana (H.E. Gates) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria petrophila subsp. petrophila  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria petterssonii Hildm. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria pfeifferi Booth ex Scheidw. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pfeifferiana de Vriese | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria phaeacantha Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria phaeotricha Monv. ex Labour. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria phantasma Sotom. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria phellosperma Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria phitauiana (E.M. Baxter) Werderm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria phymatothele A. Berger | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria picta Meinsh. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria picta subsp. viereckii (Boed.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria picturata Labour. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pilcayensis Bravo | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pilispina J.A. Purpus | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria pitcayensis Bravo | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria plaschnickii Otto | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria plecostigma Meinsh. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pleiocephala Regel & Klein | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria plinthimorpha Jacobi | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria plumosa F.A.C. Weber | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria polyacantha Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria polyactina Ehrenb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria polycentra A. Berger | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria polycephala Muehlenpf. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria polychlora Scheidw. ex C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria polyedra Mart. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria polygona Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria polymorpha Scheer ex Muehlenpf. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria polythele Mart. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria polythele var. aciculata (Otto ex Pfeiff.) Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria polythele subsp. durispina (Boed.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria polythele subsp. obconella (Scheidw.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria polythele subsp. polythele  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria polythele var. quadrispina (Mart.) Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria polythele var. setosa (Pfeiff.) Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria polytricha Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pomacea Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pondii Greene | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pondii subsp. maritima (G.E. Linds.) D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pondii subsp. setispina (J.M. Coult.) D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria porphyracantha Jacobi | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria poselgeri Hildm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria poselgeriana J.N.Haage ex C.F.Först. & Rümpler | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria posseltiana Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria potosiana Jacobi | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pottsii Scheer ex Salm-Dyck | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria praelii Muehlenpf. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pretiosa Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria priessnitzii Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pringlei (J.M. Coult.) K. Brandegee | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria prismatica (Lem.) Hemsl. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria procera Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria prolifera (Mill.) Haw. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria prolifera subsp. arachnoidea (D.R. Hunt) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria prolifera var. arachnoidea D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria prolifera subsp. haitiensis (K. Schum.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria prolifera subsp. multiceps (Salm-Dyck) U. Guzmán | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria prolifera var. multiceps (Salm-Dyck) Borg | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria prolifera subsp. texana (Engelm.) D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria prolifera var. texana (Engelm.) Borg | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria prolifera subsp. zublerae (Repp.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria pruinosa Ehrenb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria psendofuscata Quehl | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pseudoalamensis Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pseudocrucigera R.T. Craig | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria pseudofuscata Quehl | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pseudomamillaris Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pseudopectinata (Backeb.) H.P.Kelsey & Dayton | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pseudoperbella Quehl | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pseudorekoi (Rose) Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pseudoscrippsiana Backeb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pseudosimplex W.Haage & Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria puberula Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pubispina Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pugionacantha Foerster | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pulchella Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pulcherrima Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pulchra Haw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pullihamata Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pullihamata Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pulvilligera Monv. ex C.F.Först. & Rümpler | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria punctata Labour. ex C.F.Först. & Rümpler | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria purpuracea S.Watson | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria purpurascens Ehrenb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria purpurea Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria purpusii K.Schum. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pusilla DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pusilla var. haitiensis K. Schum. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pusilla var. texana Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pycnacantha Mart. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pygmaea  | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pyramidalis Link & Otto | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pyrrhacantha Pfeiff. ex C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pyrrhocentra Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria pyrrhocephala Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria pyrrhochracantha Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria quadrata G.Don ex Loudon | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria quadrispina Mart. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria queretarica R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria radiaissima Linds. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria radians DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria radians var. echinus (Engelm.) K. Schum. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria radians var. sulcata (Engelm.) K. Schum. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria radicantissima Quehl | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria radiosa Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria radiosa K. Schum. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria radiosa var. alversonii (J.M. Coult.) K. Schum. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria radiosa var. arizonica (Engelm.) K. Schum. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria radiosa var. deserti (Engelm.) K. Schum. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria radiosa var. vivipara (Nutt.) Schelle | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria radleana K.Schum. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria radliana Quehl | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria radula Scheidw. ex C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria ramosissima Quehl | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria raphidacantha var. ancistracantha (Lem.) K. Schum. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria rayonensis Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria rayonesensis Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria rectispina (E.Y. Dawson) Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria recurva Lehm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria recurvata Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria recurvispina de Vriese | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria recurvispina Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria regia Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria rekoi Vaupel | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria rekoi subsp. aureispina (A.B. Lau) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria rekoi var. aureispina A.B. Lau | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria rekoi var. leptacantha A.B. Lau | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria rekoi subsp. leptacantha (A.B. Lau) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria rekoi subsp. rekoi  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria rekoiana R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria reppenhagenii D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria rettigiana Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria retusa Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria rhaphidacantha Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria rhodacantha Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria rhodantha Link & Otto | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria rhodantha subsp. aureiceps (Lem.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria rhodantha var. droegeana K.Schum. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria rhodantha subsp. fera-rubra (Schmoll ex R.T. Craig) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria rhodantha subsp. mccartenii D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria rhodantha subsp. mollendorffiana (Shurly) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria rhodantha subsp. pringlei (J.M. Coult.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria rhodantha subsp. rhodantha  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria rhodeocentra Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria rigidispina Hildm. ex Quehl | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria rioverdense Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria rioverdensis Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria ritteriana Boed. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria ritteriana var. quadricentralis R.T. Craig bis | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria robusta Otto ex C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria robustispina Schott ex Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria roemeri Wolfg.Krüger & W.Rischer | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria rosea Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria roseana Brandegee | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria rosensis R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria roseoalba Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria roseoalha Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria roseocentra Boed. & Ritter | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria rossiana Heinr. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria rubida Fritz Schwarz | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria rubidula Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria rubrograndis Repp. & A.B. Lau | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria rueschiana Regel | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria ruestii Quehl | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria ruficeps Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria rufidula Ehrenb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria rufocrocea Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria runyonii (Britton & Rose) Cory | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria russea A.Dietr. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria rutila Zucc. ex Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria saboae Glass | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria saboae subsp. goldii (Glass & R.A. Foster) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria saboae subsp. haudeana (A.B. Lau & K. Wagner) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria saboae f. haudeana (A.B. Lau & K. Wagner) D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria saetigera Boed. & Tiegel | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria saffordii (Britton & Rose) Bravo | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria saint-pieana Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria salm-dyckiana Scheer | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria salm-dyckiana var. brunnea Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria salmiana Fennel ex C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria saltillensis Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria sanangelensis Sánchez-Mej. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria sanchez-mejoradae R. Gonzalez G. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria sanjuanensis Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria sanluisensis Shurly | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria santaclarensis Cowper | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria sartorii J.A.Purpus | 
		Accepted | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria saxatilis Scheer | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria saxicola Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria scepontocentra Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria schaeferi Fennel in Otto & A. Dietr. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria scheeri Muehlenpf. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria scheeri var. valida Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria scheidweileriana Otto | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria scheinvariana R. Ortega & Glass in Glass | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria schelhasei Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria schelhasii var. aurihamata (Boed.) Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria schiedeana Ehrenb. ex Schltdl. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria schiedeana subsp. dumetorum (J.A. Purpus) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria schiedeana subsp. giselae Lüthy | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria schieliana H.Schick | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria schlechtendalii Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria schmerwitzii J.N.Haage ex C.F.Först. & Rümpler | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria schmidtii Sencke ex C.F.Först. & Rümpler | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria schmollii Werderm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria schumannii Hildm. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria schwarzii Shurly | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria scolymoides Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria scrippsiana (Britton & Rose) Orcutt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria seegeri Ehrenb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria seemannii Scheer | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria seideliana Quehl | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria seidelii Terscheck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria seitziana Mart. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria sempervivi DC. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria senckeana K.Schum. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria senckei Horkel ex K.Schum. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria senilis Lodd. ex Salm-Dyck | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria senilis var. diguetii Weber | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria senkii C.F.Först. ex Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria senkii C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria sericata Lem. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria setispina Engelm. ex J.M. Coult. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria setosa Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria severini Regel & Klein | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria sheldonii (Britton & Rose) Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria shurliana H.E.Gates | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria silvatica Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria similis Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria similis var. caespitosa Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria similis var. robustior Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria simplex Haw. | 
		Synonym | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria simplex Torr. & A. Gray | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria simplex var. flavescens (DC.) K. Schum. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria simpsonii (Engelm.) M.E. Jones | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria sinforosensis Linzen & R.Schumach. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria sinistrohamata Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria slevinii (Britton & Rose) Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria sneedii (Britton & Rose) Cory | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria soehlemannii W.Haage & Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria solisii (Britton & Rose) Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria solisioides Backeb. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria solitaria G.Don ex Loudon | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria sonorensis R.T. Craig | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria sororia Meinsh. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria spaethiana Späth | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria speciosa de Vriese | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria spectabilis Muehlenpf. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria sphacelata Mart. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria sphacelata subsp. viperina (J.A. Purpus) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria sphaerica A. Dietr. ex Engelm. | 
		Unresolved | 
		  | 
		TRO | 
	
	
		| Mammillaria sphaerica A. Dietr. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria sphaerotricha Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria spinaurea Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria spinii Colla ex Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria spinosa G.Don ex Loudon | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria spinosissima Lem. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria spinosissima subsp. pilcayensis (Bravo) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria spinosissima subsp. spinosissima  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria spinosissima subsp. tepoxtlana D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria splendens Ehrenb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria squarrosa Meinsh. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria stampferi Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria standleyi (Britton & Rose) Orcutt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria staurotypa C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria stella-aurata Mart. ex Zucc. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria stella-de-tacubaya Heese | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria stellaris Haw. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria stellata Haw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria stenocephala Scheidw. ex Labour. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria stipitata Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria straminea Haw. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria strobiliformis Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria strobiliformis var. durispina Quehl | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria strobiliformis var. rufispina Quehl | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria strobilina Tiegel | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria stueberi Otto | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria suaveolens C.F.Först. & Rümpler | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria subangularis DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria subcirrhifera C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria subcrocea DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria subcurvata Dieter. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria subducta (D.R.Hunt) Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria subdurispina Fritz Schwarz | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria subechinata Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria subpolyedra Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria subtetragona A. Dietr. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria subtilis Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria subulata Muehlenpf. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria subulifera Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria sulcata Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria sulcimamma Pfeiff. ex Salm-Dyck | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria sulcoglandulifera Jacobi | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria sulcolanata Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria sulphurea C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria supertexta Mart. ex Pfeiff. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria supraflumen Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria surculosa Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria swinglei (Britton & Rose) Boed. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria tacubayensis Fedde | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria tamayonis Killip ex Schnee | 
		Synonym | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria tayloriorum Glass & R.A. Foster | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria tecta Miq. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria tegelbergiana H.E. Gates ex G.E. Linds. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria tenampensis (Britton & Rose) A.Berger | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria tentaculata Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria tenuis DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria tepexicensis J. Meyrán | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria tesopacensis Craig | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria tesopacensis var. papasquiarensis Bravo ex S.Arias Montes, U. Guzman Cruz & S. Gama Lopez | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria tetracantha Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria tetracentra hort. ex Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria tetrancistra Engelm. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria texana (Engelm.) Young | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria texensis Labour. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria tezontle Fitz Maurice & B. Fitz Maurice | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria thelocamptos Lehm. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria theresae Cutak | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria thornberi Orcutt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria thornberi subsp. thornberi  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria thornberi subsp. yaquensis (R.T. Craig) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria tiegeliana Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria tinuvieliae Laferr. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria tlalocii Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria toaldoae Lehm. ex Walp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria tobuschii W.T. Marshall | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria tomentosa Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria tonalensis D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria tortolensis Pfeiff. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria triacantha DC. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria trichacantha K. Schum. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria trohartii Hildm. ex K.Schum. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria tropica Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria tuberculata Engelm. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria tuberculosa Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria turbinata Hook. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria uberiformis Zucc. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria uberimamma Monv. ex C.F.Först. & Rümpler | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria umbrina Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria uncinata Zucc. ex Pfeiff. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria unihamata Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria uniseta K.Schum. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria urbaniana Vaupel | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria vagaspina R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria valdeziana (H.Moeller) H.P.Kelsey & Dayton | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria valida Purpus | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria valida Weber | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria vallensis Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria variabilis Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria variamamma Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria varieaculeata Buchenau | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria vaupelii Tiegel | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria venusta K. Brandegee | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria verhaertiana Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria versicolor Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria verticealba Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria vetula Mart. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria vetula subsp. gracilis (Pfeiff.) D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria vetula subsp. magneticola (J. Meyrán) U. Guzmán | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria viereckii Boed. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria viescensis Rogoz. & Appenz. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria villifera Otto | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria villosa Fennel ex C.F.Först. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria viperina J.A. Purpus | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria virens Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria virginis Fittkau & Kladiwa | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria viridiflora (Britton & Rose) Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria viridis Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria viridis var. praelii (Muehlenpf.) Salm-Dyck | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria viridula Ehrenb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria vivipara (Nutt.) Haw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria vivipara var. alversonii (J.M. Coult.) L.D. Benson | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria vivipara var. radiosa Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria vivipara subsp. radiosa Engelm. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria voburnensis Scheer | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria voburnensis subsp. collinsii (Britton & Rose) U. Guzmán | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria voburnensis var. collinsii (Britton & Rose) Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria voburnensis subsp. eichlamii (Quehl) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria voburnensis var. eichlamii (Quehl) Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria voburnensis var. gerhardii Diers | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria voburnensis var. quetzalcoatl Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria voburnensis subsp. voburnensis  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria vonwyssiana Krainz | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria vonwyssii Krainz | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria vulpina Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria wagneriana Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria waltheri Boed. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria webbiana Lem. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria wegenerii Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria weingartiana Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria werdermanii H.Weiss | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria wiesingeri Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria wiesingeri subsp. apamensis (Repp.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria wiesingeri subsp. wiesingeri  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria wilcoxii Toumey ex K. Schum. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria wildiana Otto | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria wildii A. Dietr. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria williamsii Coult. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria winkleri Foerster | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria winterae Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria winterae subsp. aramberri D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria wissmannii Hildm. ex K. Schum. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria woburnensis Scheer | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria woburnensis var. collinsii (Britton & Rose) Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria woburnensis var. eichlamii (Quehl) Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria wohlschlageri Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria woodsii R.T. Craig | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria wrightii Engelm. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria wrightii subsp. wilcoxii (Toumey ex K. Schum.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria wrightii var. wilcoxii (Toumey ex K. Schum.) W.T. Marshall | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria wrightii f. wolfii D.R. Hunt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria wrightii var. wolfii (D.R. Hunt) Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria wrightii subsp. wrightii  | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria wuthenauiana Backeb. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria xaltianguensis Sánchez-Mej. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria xaltianguensis subsp. bambusiphila (Repp.) D.R. Hunt | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria xanthina (Britton & Rose) Boed. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria xanthotrica Scheidw. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria xochipilli Repp. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria yaquensis R.T. Craig | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria yucatanensis (Britton & Rose) Orcutt | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria zacatecasensis Shurly | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria zahniana Boed. & Ritter | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria zanthotricha Scheidw. | 
		Unresolved | 
		  | 
		TRO | 
	
	
		| Mammillaria zapilotensis R.T.Craig | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria zegschwitzii Pfeiff. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria zeilmanniana Boed. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria zephyranthiflora Pfeiff. | 
		Unresolved | 
		  | 
		WCSP (in review) | 
	
	
		| Mammillaria zephyranthoides Scheidw. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria zepnickii Ehrenb. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria zeyeriana Haage ex K. Schum. | 
		Accepted | 
		  | 
		TRO | 
	
	
		| Mammillaria zublerae Repp. | 
		Synonym | 
		  | 
		TRO | 
	
	
		| Mammillaria zuccariniana Mart. | 
		Synonym | 
		  | 
		TRO |