| Strophocactus | |
|---|---|
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| Strophocactus wittii | |
Scientific classification | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Order: | Caryophyllales |
| Family: | Cactaceae |
| Subfamily: | Cactoideae |
| Tribe: | Echinocereeae |
| Genus: | Strophocactus Britton &Rose[1] |
| Species | |
| Synonyms | |
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Strophocactus is agenus ofcacti in the subfamilyCactoideae.[2] Its status andcircumscription remain somewhat uncertain, with the genus containing one to three species (not always the same ones).Molecular phylogenetic data suggest that it consists of three species, including two formerly comprising the genusPseudoacanthocereus. With thiscircumscription, the species have different growth habits, but share similarities in their flowers, which are white and open at night.
As circumscribed by Korotkova et al. in 2017, the three species ofStrophocactus have tubular to funnel-shaped flowers with tubercules arranged in ribs andareoles with bristles. The flowers are white and open at night. They are followed by yellow to brown fruits. Two species (S. brasiliensis andS. sicariguensis) are scrambling or decumbent shrubs, with thin stems (up to 4.5 cm across) and tuberous roots.S. sicariguensis sometimes has flattened stem segments. The third species,S. wittii, is anepiphyte with flattened stems that cling to the trunks of trees using aerial roots.[2][3]
The genus was erected byNathaniel L. Britton &Joseph N. Rose in 1913 with only one species,Strophocactus wittii.[1][4] In 1989,David Hunt reducedStophocactus to a section of the genusSelenicereus,Selenicereus sect.Strophocactus,[1] so that the species becameSelenicereus wittii. In 2003, Ralf Bauer proposed restoring the genusStrophocactus, adding two further species (S. chontalensis andS. testudo). He excludedStophocactus from the Hylocereeae.[5] Bauer's actions were based on unpublished DNA sequence data. Amolecular phylogenetic study of theHylocereeae in 2017 showed that in neither Hunt's nor Bauer's approach wereStrophocactus andSelinicereusmonophyletic:[2]
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Selenicereus wittii formed aclade with two species then placed inPseudoacanthocereus:[2]
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Accordingly, the authors followed Bauer in placingSelenicereus wittii back inStrophocactus, but now together with the two formerPseudoacanthocereus species. Like Bauer, they excluded the revised genusStrophocactus from the Hylocereeae, placing it in the tribeEchinocereeae.[2]
According to Korotkova et al. in 2017, the genus has three species:[2]
| Image | Scientific name | Distribution |
|---|---|---|
_F._Ritter_f._boreominarum_(Rizzini_%2526_A.Mattos)_P.J.Braun_%2526_Esteves.JPG) | Strophocactus brasiliensis(Britton & Rose) S.Arias & N.Korotkova, syn.Pseudoacanthocereus brasiliensis(Britton & Rose) F. Ritter | Brazil |
| Strophocactus sicariguensis(Croizat & Tamayo) S.Arias & N.Korotkova, syn.Pseudoacanthocereus sicariguensis(Croizat & Tamayo) N.P.Taylor | Colombia, Venezuela | |
| Strophocactus wittii(K.Schumann) Britton & Rose, syn.Selenicereus wittii(K.Schumann) Rowley | North Brazil, Colombia, Ecuador, Peru, Venezuela |
Species formerly included inStrophocactus are:[2]