Opuntia flavispina, western prickly pear cactus, spines

(L Benson) BD Parfitt & Pinkava, Madrono 35(4): 348, 1988 [1989]

(see also: Opuntia flavispina Hort.Berol. ex C.F.Förster., Handbuch der Cakteenkunde. [Förster] 508, nomen nudem [1846]

Herbarium; Herbarium; Herbarium; Herbarium; Herbarium; Herbarium; Herbarium

(see also)

What is Opuntia flavispina?

Opuntia flavispina is an attractive prickly pear that has long yellow spines sweeping down from the areoles. It is medium-sized, not as tall as O. engelmannii but taller than O. phaeacantha.

Details

Plants may be approximately 1 m across and 0.5-1 m tall. The branches are ascending or prostrate with some upright branches. The obovate or oval cladodes may be 15-22 cm long and 10-20 cm wide. Primary spines are up to 7.5 cm long but are often 3 to 4 cm long. O. flavispina is characterized by a single, deflexed, long, yellow spine at many areoles. This major spine often has a burgundy base that darkens as the pads age. A much shorter secondary spine may be present. The second spine often deflexes downward more strongly than the first spine. Overall, because of the copious yellow spines, the plant often has a greenish-yellow look.

Flowers are yellow with green stigmas. Deep red fruit is roundish or barrel-shaped with a distinctly depressed umbilicus. Sometimes fruit may be longish, almost clavate. Over time the fruit becomes dull purple.

O. flavispina is hexaploid.

Other Notes

O. flavispina was published as a variety of O. engelmannii. Prior to that, it was described as a variety of O. phaeacantha. Nonetheless, we accept it as an undescribed, stand-alone species.

O. flavispina occurs sporadically in southern Arizona and adjacent Mexico.