Opuntia parryi serpentina cristata

Opuntia parryi serpentina cristataopuntia beavertail Also known as beaver tail cactus grows in very arid plains and valleys. This is a smaller prickly pear, branching upwards to 30cm (60 cm) high in clumps up to 90cm (1. 2 m) in diameter. Stem: Oval to roundish blue gray green, with a blush of purple pigmentation (due to the presence of betacyanins pigments) that vary in function of temperature, glabrous or slightly covered with a velvety pubescence, smooth to wrinkled in dry

opuntia beavertail

Also known as beaver tail cactus grows in very arid plains and valleys. This is a smaller prickly pear, branching upwards to 30cm (60 cm) high in clumps up to 90cm (1.2 m) in diameter.
Stem: Oval to roundish blue-gray-green, with a blush of purple pigmentation (due to the presence of betacyanins pigments) that vary in function of temperature, glabrous or slightly covered with a velvety pubescence, smooth to wrinkled in dry conditions. New pads stretching from the lower areas of the plant.
Spines: Usually spineless, if a few spines are present they are confined to the upper rim of the pad.
Flower: 5cm in diameter and 6cm long; open from spring to early summer. They are intensely rose purple with deep magenta-red filaments and white or pink style, stigma is white. (yellow blooming plant are also know).

Some of the information in this description has been found at desert-tropicals.com, llifle.com and cactus-art.biz