Ariocarpus trigonus var. horacekii Halda in Cactaceae etc. 7: 97. 1997 Ariocarpus trigonus var. horacekii Halda in Cactaceae etc. 7: 97. 1997is basionym for Ariocarpus elongatus subsp. horacekii (Halda) Halda in Acta Mus. Richnov., Sect. Nat., 5: 36. 1998Taxon for this nameAriocarpus trigonus var. horacekii Halda