Opuntia polyacanthaHaw.

Plains Pricklypear

WFO wfo-0001287039 Accepted WFO 2026-06 8 photographs CC0 / CC BY

Plate 1 figs. a–h

Opuntia polyacantha, photographed by Cecelia Alexander
fig. a Cecelia Alexander, CC0 1.0 / 2022-05-29 / obs. 201718399
Opuntia polyacantha, photographed by James M. Maley
fig. b James M. Maley, CC BY 4.0 / obs. 204814436
Opuntia polyacantha, photographed by Laura Gaudette
fig. c Laura Gaudette, CC BY 4.0 / obs. 203385828
Opuntia polyacantha, photographed by John Gaskin
fig. d John Gaskin, CC0 1.0 / obs. 199822978
Opuntia polyacantha, photographed by Cecelia Alexander
fig. e Cecelia Alexander, CC0 1.0 / obs. 201332760
Opuntia polyacantha, photographed by Cecelia Alexander
fig. f Cecelia Alexander, CC0 1.0 / obs. 201105933
Opuntia polyacantha, photographed by James M. Maley
fig. g James M. Maley, CC BY 4.0 / obs. 204814640
Opuntia polyacantha, photographed by John Gaskin
fig. h John Gaskin, CC0 1.0 / obs. 201715218

Every figure is a research-grade observation under CC0, CC BY or CC BY-SA, rehosted with the photographer’s name, the licence and the observation it came from. Photographs under a NonCommercial licence are excluded from this site and are never stored, which costs us a great many pictures and is not negotiable.

Confused withby our own model

These are not lookalikes we guessed at. Each one is a species our identification model genuinely mistook for this plant, and how many times. The error rate is published.

Flowering n = 2,548 observations

Peak flowering in Jun, from 2,548 community-annotated observations worldwide. This is a global aggregate, not a forecast for your garden: the same species flowers on different dates in different hemispheres, and citizen-science records cluster near cities, at weekends, and in spring. Where a species has fewer than 30 annotated records we do not draw this chart at all.

Also published as 65 synonyms

A synonym is not an error. It is a record of botanists disagreeing, in print, about where this plant belongs. Each of these was somebody’s considered answer.

  • Cactus ferox Nutt.
  • Opuntia arrastradillo Backeb.
  • Opuntia barbata K.Brandegee ex J.A.Purpus
  • Opuntia barbata var. gracillima K.Brandegee ex J.A.Purpus
  • Opuntia erinacea Engelm. & J.M.Bigelow
  • Opuntia erinacea subsp. hystricina (Engelm. & J.M.Bigelow) Lodé
  • Opuntia erinacea var. erinacea
  • Opuntia erinacea var. hystricina (Engelm. & J.M.Bigelow) L.D.Benson
  • Opuntia erinacea var. paucispina Dunkle
  • Opuntia erinacea var. rhodantha (K.Schum.) L.D.Benson
  • Opuntia erinacea var. ursina (F.A.C.Weber) Parish
  • Opuntia erinacea var. utahensis (Engelm.) L.D.Benson
  • Opuntia erinacea var. xanthostemma (K.Schum.) L.D.Benson
  • Opuntia heacockiae Arp
  • Opuntia hystricina Engelm. & J.M.Bigelow
  • Opuntia hystricina var. bensonii Backeb.
  • Opuntia hystricina var. nicholii (L.D.Benson) Backeb.
  • Opuntia hystricina var. ursina (F.A.C.Weber) Backeb.
  • Opuntia juniperina Britton & Rose
  • Opuntia media Haw.
  • Opuntia missouriensis DC.
  • Opuntia missouriensis f. albispina (Engelm. & J.M.Bigelow) Schelle
  • Opuntia missouriensis f. trichophora (Engelm. & J.M.Bigelow) Schelle
  • Opuntia missouriensis var. albispina Engelm. & J.M.Bigelow

and 41 more.

Sourcesevery claim on this page

  1. World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
  2. iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.

We publish what we can source and we say so when we cannot. This page has no care advice, no toxicity claim and no native range, because we do not yet have those from a source we can cite.