Mammillaria prolifera var. texana (Engelm.) Borg, Cacti

Mammillaria texana (Engelm.) M.J.Young, Familiar Lessons Bot. 279.1873 (“ Mammilaria Texana ”).

Mammillaria pusilla var. texana Engelm., Proc. Amer.Acad.Arts Sci. View in CoL 3:261.1856 (“ Mamillaria pusilla var. Texana ”); Engelmann in Emory, Rept. U.S. Mex. Bound. 2(1):5, t. 5. 1859 (“ Mamillaria pusilla var. Texana ”).

Mammillaria prolifera var. texana (Engelm.) Borg, Cacti View in CoL 316. 1937.

TYPE: MEXICO. Santa Rosa , 1853, J.M. Bigelow s.n. ( LECTOTYPE (second step), designated here: MO [ MO-2035110 as image!]) .

Although this species is presented simply as “ M [ ammillaria] Texana ” in Young’s (1873) flora, it is a new combination and change in status based on M. pusilla var. texana (see e.g., IPNI 2021; Tropicos 2021). When Engelmann (1856) published the varietal name, he indicated that he was validating it in advance of a more elaborate illustrated treatment of the Cactaceae for the “Reports of the Boundary Commission and those of the Pacific Railroad Surveys.” In the original protologue, Engelmann (1856) states only “On the Rio Grande, near Eagle Pass and southward” and does not provide the name of a collector or collectors yet when he ( Engelmann 1859) treated this taxon again in Cactaceae of the Boundary, he wrote “From Eagle Pass to Santa Rosa, Dr. Bigelow, and, according to Dr.Poselger, common on the Rio Grande below” thereby indicating that collections by Bigelow and Poselger constitute original material. The plate ( Engelmann 1859) accompanying this later description, however, is not original material as it was completed several years after the varietal name was first validly published. Interestingly, Young’s (1873) description is not copied from the protologue ( Engelmann 1856), but rather the description published in the Cactaceae of the Boundary ( Engelmann 1859). This suggests that Young (or Buckley) had a copy of the latter but not the former publication.

When Young (1873) published the combination Mammillaria texana , she cited only a collection made “Along the Rio Grande” by Dr.Poselger and not one made by Dr. Bigelow. This is not in and of itself a lectotype designation because the word type or its equivalent was not used. Coulter (1894) effectively selected a lectotype (first-step) when he wrote “Type, Bigelow specimens in Herb. Mo. Bot. Gard.” Benson (1982), who discussed the typification of most cacti of the U.S.A. and who had access to the Engelmann collection, however stated “original material not found, Mo.” A lectotype (second-step) is designated here because Coulter did not specify a single collection (viz., “specimens”) and no material annotated by him has been located.