This name is a synonym of Mammillaria longimamma DC..
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 5104380) with original publication details: Enum. Diagn. Cact. 23 1837.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:151815-2.
This name was in version 1 of The Plant List, record tro-5104380.