Coryphantha pachanoi (Britton & Rose) Friedrich & Rowley

San Pedro Cactus

Body cylindrical, becoming large to over 5 m tall, branches erect. Ribs 6-8, rounded. Spines few or absent, yellowish brown. Flowers white. [Trichocereus pachanoi Britton & Rose]


Other cylindrical nocturnal species with flowers about 18 cm long opening at night and remaining open for the following day, keyed out above, include 3 species from Argentina: E. spachiana (Lem.) Friedrich & Rowley, E. schickendantzii (F.A.C. Weber) and E. terscheckii (Pfeiff.) Friedrich & Rowley while E. chiloensis (Colla) Friedrich & Rowley from Chile has smaller flowers about 10 cm long that remain open for several days.

Source: Thompson, A, ; Forbes, S.; Spencer, R. (1997). Cactaceae. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 2. Flowering plants. Dicotyledons. Part 1. The identification of garden and cultivated plants. University of New South Wales Press.

kingdom Plantae
phylum   Tracheophyta
class    Magnoliopsida
superorder     Caryophyllanae
order      Caryophyllales
family       Cactaceae
genus        Coryphantha (Engelm.) Lem.