CNPS

CNPS Rare Plant Inventory



Taxon Details

Chorizanthe aphanantha

Irish Hills spineflower

  View Report   Copy Link Calflora eFlora CCH CalPhotos iNaturalist
Photo of Chorizanthe aphanantha
© 2019 Keir Morse 		Photo of Chorizanthe aphanantha
© 2019 Keir Morse 		Photo of Chorizanthe aphanantha
© 2019 Keir Morse

Taxon Summary:

Chorizanthe aphanantha, commonly known as Irish Hills spineflower, is a annual herb in the Polygonaceae that is found only in California. It occurs within Chaparral (edges, openings), and Coastal scrub, growing at elevations from 100 to 370 meters. Chorizanthe aphanantha is ranked 1B.1, Plants Rare, Threatened or Endangered in California and Elsewhere; Seriously threatened in California.

  Classification

Scientific Name:
Chorizanthe aphanantha K.M. Nelson & D.J. Keil
Common Name:
Irish Hills spineflower
Family: Polygonaceae
Element Code: PDPGN04110
USDA Plants Symbol:
Synonyms/Other Names:
Name Status: JEF, FNA, POWO,
IPNI, Tropicos

  Conservation Status

CA Rare Plant Rank: 1B.1
Fed List: None
State List: None
Global Rank: G1
State Rank:
 S1
Other Status: BLM_S; SB_SBBG
CRPR Changes:
added to 1B.1 on 2019-06-12
Add Date: 2019-06-11
Date Edited: 2024-11-05

  Ecology and Life History

Lifeform: annual herb
Blooming Period: Apr-Jun
JFMAMJJASOND
Elevation:
100 - 370 meters
330 - 1215 feet
General Habitats:
  • Chaparral (edges, openings)
  • Coastal scrub
Microhabitat Details:
Microhabitat:
  • Gravelly
  • Rocky
  • Serpentine

  Notes

Notes:
Similar to and co-occurs with C. breweri; differentiated in having perianth 1.5-1.7 mm long (vs. 2-5 mm) and involucre green at flowering (vs. red to purple at flowering in C. breweri).
Threats:
Taxonomy:

  Threat List Data from the CNDDB

Threat List Total: 0
Total EOs % of EOs
EOs with Threat Listed: 0 %
THREAT LIST:

 

  Occurrence Data from the CNDDB

Total Occurrences: 3
Element Occurrence Ranks:
A B C D X U
0 0 0 0 0 3
Occurrence Status:
Historical >20 Years 0
Recent <=20 Years 3
Presence:
Presumed Extant 3
Possibly Extirpated 0
Presumed Extirpated 0

  Location

California Endemic:
California Island:
States: Name (Code)
California (CA)
California Counties and Islands: Name (Code)
San Luis Obispo (SLO)
Quads: Name (Quad Code)
Pismo Beach (3512026), San Luis Obispo (3512036)
Notes:
Definitions of codes following a county and/or quad:
* Presumed extirpated
(?) Occurrence confirmed, but possibly extirpated
Quad and county data is imported from the CNDDB. Species may be present in other areas where conditions are favorable. These data should NOT be substituted for pre-project review or for on-site surveys.
Regional Map

  Map

Presumed Extant
Click on quad for name. Hold Shift Key to use mouse scroll wheel

  Selected References

CNPS Status Review: Proposed Addition to CRPR 1B.1, G1 / S1 (2019)
Original Description: Madroño 65(4):184-191 (2018)

Go to top


Suggested Citation:
California Native Plant Society, Rare Plant Program. 2025. Rare Plant Inventory (online edition, v9.5.1). Website https://www.rareplants.cnps.org [accessed 27 January 2025].
}