Opuntia aurea (Creeping beavertail)

Opuntia aurea McCabe ex E. M. Baxter 1933

Creeping beavertail, yellow beavertail

Kingdom	Plantae	Plants, but not fungi, lichens, or algae
Subkingdom	Tracheobionta	Vascular plants—plants with a “circulatory system” for delivering water and nutrients
Division	Magnoliophyta	Flowering plants, also known as angiosperms
Class	Magnoliopsida	Dicotyledons—plants with two initial seed leaves
Subclass	Caryophyllidae	Cacti, many other succulents, carnivorous plants, and leadworts
Order	Caryophyllales	Includes cacti, carnations, amaranths, ice plants, and many carnivorous plants
Family	Cactaceae	Succulent (water-storing) plants, often spiny
Genus	Opuntia	Prickly pears
Species	aurea	Golden

About plant names...

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,^[1] 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.

By Howard Cheng. This picture was probably taken at the Conejo Valley Botanic Garden, because the cactus is not found in the wild in California. The photo is identified as Opuntia basilaris var. aurea, but the more recently accepted name is Opuntia aurea.

References:

Anderson, Edward F., The Cactus Family, Timber Press, 2001, p. 488

Online References:

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 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

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

Opuntia basilaris Engelm. & J.M. Bigelow var. aurea (E.M. Baxter) W.T. Marshall

Opuntia erinacea Engelm. & J.M. Bigelow ex Engelm. var. aurea (E.M. Baxter) S.L. Welsh

Opuntia aurea description by Thomas H. Kent, last updated 25 May 2020.

6/3/2009 · Kolob Canyons, Zion National Park, Utah
≈ 6 × 5" (14 × 13 cm) ID is uncertain

With some introgression. · 6/3/2009 · Kolob Canyons, Zion National Park, Utah
≈ 11 × 8" (29 × 19 cm) ID is uncertain

With significant introgression. · 6/3/2009 · Kolob Canyons, Zion National Park, Utah
≈ 17 × 12" (44 × 29 cm) ID is uncertain

With some introgression. · 6/3/2009 · Kolob Canyons, Zion National Park, Utah
≈ 17 × 11" (43 × 28 cm) ID is uncertain

Range:

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