California cholla

Cereus californicus Torrey & A. Gray, Fl. N. Amer. 1: 555. 1840; Opuntia californica (Torrey & A. Gray) Coville 1899, not Engelmann 1848 (provisional name)

Shrubs, decumbent to erect, essentially trunkless, 0.3-2.5 m. Stem segments green to purplish green, 6-30 × 1.5-2.5 cm; tubercles prominent, oval to elongate-elliptic, 0.7-3 cm, sometimes appearing as ribs; areoles elliptic, 4.5-5 × 3-3.5 mm; wool tan, aging dark gray. Spines (0-)7-13(-20) per areole, at most areoles, rarely obscuring stems, yellow to orange-brown with yellow tips, aging dark gray, subequal or 1-6(-7) much longer to 3 cm; sheaths whitish or gold to brown, moderately loose. Glochids yellow-tan to red-brown in dense adaxial crescent and scattered, stouter ones at basal margins. Flowers: inner tepals yellow to greenish yellow; outer ones tipped red, 15-30 mm; filaments green or yellow; anthers yellow; style light green or cream-white (rarely pinkish) apically; stigma lobes cream-white to yellow. Fruits green to yellowish, drying gray-tan, short top-shaped to subspheric, 15-32 × 13-26 mm, leathery-dry, tuberculate, few spined or spineless; proximal tubercles longest; umbilicus deep; rim slightly flanged; areoles 13-30. Seeds tan, squarish to angular in outline, warped, (4-)5-7 × 4-5 mm, sides with 2-4 deep depressions; girdle smooth.

Varieties 4 (2 in the flora): California; Mexico.