Opuntia chlorotica santa-rita, Santa-Rita Purple Pricklypear

Opuntia chlorotica var. santa-rita at Santa Rita Mountains, AZ
Opuntia chlorotica santa-rita

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

Original Description

What is Opuntia chlorotica var. santa-rita?

O. chlorotica var. santa-rita, the Santa-Rita purple prickly pear, is one of three varieties in the O. chlorotica complex—together with var. chlorotica and var. gosseliniana. It was clarified and united with O. chlorotica by Ferguson 1988, and is reported to be closely related by other studies. Plants are noted for vivid purplish pads in cool or drought seasons, robust clumping shrubs, and bright yellow spring flowers; the taxon is iconic in the Tucson area and widely cultivated.

Details

Shrubs: Usually 1–1.5 m tall, forming dense, upright clumps with short trunks and ascending branches. Cladodes: Broadly circular to suborbicular (rarely obovate), mostly 12–18 cm across; glaucous blue-green that turns violet to magenta with cold or stress; margins slightly scalloped. Areoles: Distinct and slightly raised, bearing tan to brown glochids; spination variable by areole position. Glochids: Fine, barbed, tan to rusty; persistent. Spines: Often absent on lower areoles; when present, typically 1–4 per areole, longer on upper pads, straight to slightly curved, white to yellowish or pale brown, c. 2–3 cm (occasionally longer). Flowers: Bright yellow, c. 6–9 cm across, sometimes with faint reddish basal suffusion; filaments and style pale; stigma lobes pale green to whitish. Fruits: Ovoid, depressed at the apex, purplish outside with greenish pulp; areoles concentrated toward the apex. Seeds: Pale, lenticular, typical for the complex. Cytology: Diploid (2n = 22).

Range & Habitat

Common in south-central Arizona and northern Sonora, especially around Tucson, the Santa Rita and Sierrita mountains, and westward toward Ajo; on rocky slopes, bajadas, and desert scrub, roughly 800–1500 m elevation, often with Larrea and Ambrosia on well-drained soils.

Similar or Sympatric Species

Opuntia chlorotica var. chlorotica — greener pads, larger fruit.
Opuntia chlorotica var. gosseliniana — smaller pads, slender fruits.
Opuntia macrocentra — red-centered flowers, darker pads.
Opuntia engelmannii — taller shrubs, broader joints.
Opuntia phaeacantha — low, variable, stout spines.
Opuntia setispina — gray pads, usually white spines.

Other Notes

Long grown in cultivation for its winter color; stress deepens the purple hue. Historical notes place type material in the Santa Rita Mountains, and “All gradations of spine characters may be found between this and the typical, very spiny Opuntia chlorotica.” GenBank locus JF787617.1.

For more information, see:

Ferguson, Opuntia macrocentra Eng. and Opuntia chlorotica Eng. & Big.; Shaw & Ferguson (2019), Tucson area Opuntia, the prickly pears; Majure et al. (2012), Phylogeny of Opuntia s.s.

6 thoughts on “Opuntia chlorotica santa-rita, Santa-Rita Purple Pricklypear”

  2. Pougnier

    Hi!
    I am obsessed with finding an O. Santa Rita with perfectly round cladodes. Do you have any suggestions? They seem rather more rare than subjects with slightly ovoid ones.

  3. Winston James

    Absolutely gorgeous, and I do love variations .

    I live in the UK, but will love to get my hands on a few of these pads. Any ideas ?

  4. Judy Kugle

    I collected mine from a small paddle in Palm Springs CA. It now lives In Nacogdoches Texas and is very cold hardy. It has gone through 4 years of extreme weather from 115 to teens including snow. I’ve shared paddles so it’s small but bloomed for the first time this year.

  6. Joseph

    Yes. You can use the photos. If the photos have a photographer listed, please note that when you use the phto. Most photos do not have anyone listed and you are free to use them.

Leave a Reply

Your email address will not be published. Required fields are marked *