Peniocereus (A.Berger) Britton & Rose, Contributions from the United States National Herbarium 12(10): 428. 1909.
Cullmannia Distef., Kakteen Sukk. 7 : 8. 1956.
Arias, S. & al. 2005. Phylogenetic relationships in Peniocereus (Cactaceae) inferred from plastid DNA sequence data. Journal of Plant Research 118(5): 317-328. (reinstate the genus Nyctocereus)
Peniocereus is a genus of vining cacti, comprising about 18 species, found from the southwestern United States and Mexico. They have a large underground tuber, thin and inconspicuous stems.
The following genera have been brought into synonymy with Peniocereus:
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