Molecular phylogenetic data suggest that it consists of three species, including two formerly comprising the genus Pseudoacanthocereus.

With this circumscription, 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 of Strophocactus have tubular to funnel-shaped flowers with tubercules arranged in ribs and areoles with bristles.

Two species (S. brasiliensis and S. sicariguensis) are scrambling or decumbent shrubs, with thin stems (up to 4.5 cm across) and tuberous roots.

The third species, S. wittii, is an epiphyte with flattened stems that cling to the trunks of trees using aerial roots.