Rapicactus is a genus of cactus in the tribe Cacteae, subfamily Cactoideae. It has been synonymized with Turbinicarpus but molecular phylogenetic studies have supported its monophyly and separation from that genus.[1]
The genus Rapicactus was proposed in 1942 by Buxbaum and Oehme.[2] It was characterized by having thick roots with a constriction above forming a neck. However, most subsequent treatments sank the genus into a broadly circumscribed genus Turbinicarpus. The circumscription of Turbinicarpus has been described as "remarkably unstable", with species regularly transferred to other genera.[1] The broad circumscription of Turbinicarpus was recognized as polyphyletic by Hunt in 2016.[3] A phylogenetic study published in 2019 showed that a monophyletic Rapicactus was sister to Acharagma, separated from a monophyletic Turbinicarpus:[1]
Three species of other genera
Rapicactus
Species of other genera
Species of other genera
Turbinicarpus s.s.
As of March 2022, Plants of the World Online accepted four species:[4]
Rapicactus is a genus of cactus in the tribe Cacteae, subfamily Cactoideae. It has been synonymized with Turbinicarpus but molecular phylogenetic studies have supported its monophyly and separation from that genus.
