Opuntia aurea McCabe ex E. M. Baxter 1933
Opuntia basilaris Engelm. & Bigelow var. aurea (E.M. Baxter) W.T. Marsh.
Opuntia erinacea Engelm. & Bigelow ex Engelm. var. aurea (E.M. Baxter) S.L. Welsh
Creeping Beavertail, Yellow Beavertail
These cacti are found only in the southern part of Utah and northern Arizona, where they are native and often quite abundant.
Identification: These plants are low—4-12" (10-30 cm)—lying on or growing close to the ground. The stem segments are ellipse- or egg-shaped, 1¾-4" (5-10 cm) × 1-2" (3-6 cm) across. The glochids, tiny hairlike clusters of needles, are tan or brown, and ⅛" (3 mm) long. Spines are absent, though varying degrees of introgression—natural hybridization—have produced plants that often have spines, especially along the outer edges of the stem segments. Flowers are yellow or pink, and 1¾-3" (5-7.5 cm) in size. Fruits are ½-⅞" (1.5-2.5 cm) in diameter, green, lacking spines. See this Opuntia comparison table.
Opuntia aurea on Opuntiads of the USA
Opuntia aurea on CactiGuide.com
Opuntia aurea on www.americansouthwest.net
Opuntia aurea on eFloras
Opuntia aurea on SEINet—the Southwest Environmental Information Network (includes locations of sightings)
Opuntia aurea on Discover Life
1The pink coloration is also due to introgression. (Thanks to Tony Frates for correctly identifying the pink ones.)
Opuntia aurea description by Thomas H. Kent, last updated 16 Aug 2013.