Taxon Report

Calicium adspersum Pers.

spiral-spored gilded-head pin lichen

Print Report

Taxon Summary

Calicium adspersum, commonly known as spiral-spored gilded-head pin lichen, is a crustose lichen (epiphytic) in the Caliciaceae that is found in California and elsewhere. It occurs within Lower montane coniferous forest, and North Coast coniferous forest, growing at elevations from 200 to 200 meters. Calicium adspersum is ranked 2B.2, Plants Rare, Threatened, or Endangered in California, But More Common Elsewhere; Moderately threatened in California.

Classification


Scientific Name:	Calicium adspersum Pers.
Common Name:	spiral-spored gilded-head pin lichen
Family:	Caliciaceae
Element Code:	NLT0005640
USDA Plants Symbol:	CAAD4
Synonyms/Other Names:

Ecology and Life History


Lifeform:	crustose lichen (epiphytic)
Blooming Period:
Elevation:	200-200 (655-655)
General Habitats:	Lower montane coniferous forest, North Coast coniferous forest
Microhabitat:
Microhabitat Details:	Often restricted to old-growth bark of conifers that are over 200 years in age

Conservation Status


CA Rare Plant Rank:	2B.2
Global Rank:	G3G4
State Rank:	S1
State List:	None
Fed List:	None
Other Status:	USFS_S
CRPR Changes:	added to 2B.2 on 2014-03-01

Occurrence Data from the CNDDB


Total Occurrences:	1
Element Occurrence Ranks:
Excellent (A)	0
Good (B)	0
Fair (C)	0
Poor (D)	0
None (X)	0
Unknown (U)	1

Location


California Endemic: False
California Counties and Islands: Name (Code)
Del Norte (DNT)
Quads: Name (Quad Code)
Crescent City (4112472), Hiouchi (4112471), Sister Rocks (4112462)

Threat List Data from the CNDDB


Threat List Total:	2
EOs with Threat Listed:	Total EOs	% of EOs
	1	100 %
Improper burning regime	1	100%
Logging	1	100%

Notes



Known in CA only from Jedediah Smith Redwoods SP. Host conifers could include Abies grandis, Pseudotsuga menziesii, Sequoia sempervirens, and Thuja plicata.
Threats:
Historically threatened by logging. Possibly threatened by alteration of fire regimes.
Taxonomy:
Similar to C. lenticulare; however, C. adspersum is the only species of Calicium currently known from the Pacific Coast with a yellow pruina.

Selected References

Calicium adspersum profile for potential Species of Conservation Concern evaluation (2018)

Bulletin of the California Lichen Society 13(2):51-54 (2006) for CALS Conservation Committee sponsorship

Citation California Native Plant Society, Rare Plant Program. 2025. Rare Plant Inventory (online edition, v9.5.1). Website https://www.rareplants.cnps.org [accessed 30 October 2025].