Slender stems and large flowers
Stems initially grow upright, then lean on surrounding vegetation or hang as they lengthen. Numerous low ribs with closely spaced areoles divide their surface. Flowers are very large relative to stem diameter, with a long tube and widely opening pale tepals. Fruits remain fleshy and bear spines that detach readily from the skin. [Britton and Rose 1920]
Position in phylogenetic research
Plastid DNA analysis showed that the former broad circumscription of Peniocereus combined several separate lineages. Material of P. serpentinus from Michoacán and Oaxaca fell outside the group representing Peniocereus in the narrow sense. This supported reinstating Nyctocereus for the species. A similar slender habit can therefore occur in different branches of cactus relationships. [Arias et al. 2005]
The genus in nature and cultivation
POWO distinguishes the native Mexican range from introductions in KwaZulu-Natal, New South Wales and Queensland. The species has also long been grown in gardens. Experimental micropropagation through areole activation produces new shoots in tissue culture, with details of the tested procedure given in the species account. [2-WWW] [Britton and Rose 1920] [Pérez Molphe Balch et al. 1998]