Pelecyphora, commonly known as pincushion cactus or foxtail cactus, is a genus of small cacti in the family Cactaceae, native to Mexico and the United States. Plants are spherical to club-shaped stem succulents, typically reaching no more than 6 cm (about 2.4 inches) in diameter, and are gray-green in colour. A distinctive feature is the arrangement of spines in a pectinate, or comb-shaped, pattern on flattened tubercles (warts). Branching is sparse and occurs only in older specimens.
Flowers emerge individually from short furrows on the upper surfaces of the youngest areoles and are bright purple, approximately 3 cm long. The greenish fruits dry at maturity, releasing small black seeds into the crown wool; in nature, seeds are dispersed primarily by rainwater washing them free. The genus encompasses roughly 20 species, though its boundaries have been the subject of ongoing taxonomic debate — some classifications have merged Pelecyphora with closely related genera such as Escobaria.
Notable members include Pelecyphora missouriensis (Missouri foxtail cactus), which is widespread in grassland and forest habitats west of the Mississippi River, and Pelecyphora strobiliformis, listed alongside P. aselliformis on Appendix I of the Convention on International Trade in Endangered Species (CITES).
Etymology
The genus name Pelecyphora derives from the Greek words pelekys (hatchet or axe) and phoros (bearing), referring to the hatchet-shaped arrangement of the pectinate spines on the tubercles.
Distribution
Pelecyphora species are native to Mexico and the United States. Pelecyphora missouriensis is widespread in grassland and forest habitats west of the Mississippi River, and Pelecyphora vivipara ranges across much of the United States and into Canada.
Conservation
Pelecyphora aselliformis and Pelecyphora strobiliformis are both assessed as Least Concern on the IUCN Red List. Despite this assessment, both species are listed in Appendix I of CITES (the Convention on International Trade in Endangered Species), which prohibits commercial international trade; this listing reflects the threat posed by collection from wild populations for the horticultural trade.
Cultivation
Pelecyphora species are grown as ornamental cacti by collectors. As desert cacti from semi-arid Mexican and North American habitats, they require excellent drainage, a gritty or mineral-based substrate, and bright light. Watering should be minimal during winter dormancy and moderate during the growing season. Both P. aselliformis and P. strobiliformis are subject to CITES Appendix I restrictions, meaning specimens for cultivation must be demonstrably nursery-propagated rather than wild-collected.
