Description

Key Characters:

Growth Form: Shrubs, vinelike, scandent, terrestrial, hemi-epiphytic, epiphytic, or epipetric, sparingly to abundantly branched, often succulent, branches clustered at nodes.

Stems: Stems segmented or unsegmented, usually bright green or bluish green to purplish, slender cylindric [flattened and leaflike in some epiphytic species], 100–500 × 0.8–5[–30] cm, glabrous, ribs 3–8[–12] [or 2-winged in some epiphytic species], prominent and acute to low and rounded, rib crests straight to somewhat undulate [toothed, notched, or if stems winged and leaflike, then conspicuously lobed], areoles [10–]15–25[–60] mm apart along ribs, small, orbicular, woolly with short white hairs, areolar glands absent, cortex thin and somewhat mucilaginous in thicker stems, pith usually not mucilaginous.

Roots: Roots diffuse or adventitious along stems.

Leaves: Leaves modified into spines or ocassionally absent. Spines 1–18 per areole [absent on adult stems of epiphytic species], yellow, blackish, or brown [white, greenish, or reddish], lateral on stems, bristles hairlike, acicular, or conic, 1–15[–20] mm, soft to hard; radial spines [0–]1–18, straight to twisted, usually more slender and flexible than central spines; central spines [0–]1[–4] per areole, often not distinguishable from radials, straight [to bent], 1[–15] mm. Stipules absent.

Flowers: Flowers solitary; floral areoles minutely scaly (scales absent in S. spinulosus) with hairs and bristles or spines; spines acicular or flexible, hairlike. Flowers bisexual (perfect), nocturnal, lateral on stems, often fragrant, typically with a long tube funnelform to salverform. Outer tepals usually widely spreading when fully open, yellow, orange, brownish, or greenish [to red or purple], linear to narrowly oblanceolate; inner Tepals ascending to spreading when fully open, white [rarely colored], broad. Stamens numerous, inserted in the throat of the receptacle tube; anthers dithecal, longitudinally dehiscent. Ovary inferior, very rarely superior, 3-carpellate to many-carpellate, 1-celled; ovules numerous, on parietal placentas, usually campylotropous, with foliaceous scales; style 1; stigma lobes 2 to numerous, papillate.

Fruit: Berries usually red; spheric or oblong to ovoid; 5–9 cm; fleshy; hairs and bristles deciduous; scales; if present; minute; not conspicuous. Seeds numerous; shiny black; ovate–reniform.

Ploidy:

Habitat:

Elevation Range: