Cryptic Paw Lichen
Scientific Name: Nephroma occultum
Other/Previous Names: Cryptic Paw
Taxonomy Group: Lichens
COSEWIC Range: British Columbia
COSEWIC Assessment Date and Status Change: May 2019
COSEWIC Status: Threatened
COSEWIC Status Criteria: A3c+4c
COSEWIC Reason for Designation: This leafy lichen is endemic to western North America. In Canada the total estimated population is approximately 12,000 individuals. The species has specific habitat requirements, growing in humid old coastal and interior cedar-hemlock forests that have depressions kept moist by input from groundwater. The lichen reproduces only by vegetative propagules with limited capability for dispersal. The species is threatened by habitat loss as a result of forest harvesting, and by climate change leading to altered patterns of winter precipitation and warmer drier summers that can enhance the frequency and severity of fires. The IUCN Threats assessment calculator result for this species was Very High to High.
COSEWIC History of Status Designation: Designated Special Concern in April 1995 and in April 2006. Status re-examined and designated Threatened in May 2019.
SARA Status: Schedule 1, Special Concern
Date of Listing (yyyy-mm-dd): 2007-12-13
Please note that this information is provided for general information purposes only. For the most up to date and accurate list of species listed under the Species at Risk Act, please see the Justice Laws Website.
Image of Cryptic Paw Lichen
The lichen is leafy, rounded and loosely pressed in appearance. It measures 3 to 7 cm across. The upper surface is pale yellowish- to greenish- or bluish-grey, while the lower surface is pale tan at the edges, blackish toward the centre. Both sides are dull and naked. The bottom is finely wrinkled. A lichen is a plant organism composed of a fungus and an alga in symbiotic association.
Distribution and Population
The Cryptic Paw Lichen is found only in the Pacific Northwest of North America. There are 28 locations in which the lichen is known to occur (21 in British Columbia, five in Oregon, two in Washington). The density of these lichens ranges from distinctly sparse to locally frequent (20 thalli (plant-bodies) per square metre considered frequent). Only one or two thalli per site were recently found in more than half the B.C. sites, but virtually all the plants were vigourous.
The Cryptic Paw Lichen is restricted to humid old-growth forests at lower elevations in mountainous regions. It appears to have very specific ecological requirements, which include high humidity and moderate summer temperatures.
The species reproduces through spores (reproductive cells). Spores grow to become individuals identical to the parents, in a suitable habitat. Splashing rain carries spores short distances. Migrating birds and other animals disperse spores over longer distances.
Continued logging of B.C.'s old-growth forests is causing the species' steady, seemingly permanent, decline. Once the plant has disappeared from a site, it is not likely to reoccur in secondary-growth replacement forests. The species' limited distribution results mostly from its specific climatic requirements. Natural causes of mortality are competition from other lichens and forest defoliation by insects.
The Cryptic Paw Lichen is protected under the federal Species at Risk Act (SARA). More information about SARA, including how it protects individual species, is available in the Species at Risk Act: A Guide.
Provincial and Territorial Protection
Team for the Cryptic Paw Lichen
Brenda Costanzo - Chair/Contact - Government of BC
Phone: 250-387-9611 Fax: 250-356-9145 Send Email
PLEASE NOTE: Not all COSEWIC reports are currently available on the SARA Public Registry. Most of the reports not yet available are status reports for species assessed by COSEWIC prior to May 2002. Other COSEWIC reports not yet available may include those species assessed as Extinct, Data Deficient or Not at Risk. In the meantime, they are available on request from the COSEWIC Secretariat.
12 record(s) found.
- COSEWIC Status Reports (2 record(s) found.)
- COSEWIC Assessments (1 record(s) found.)
- Response Statements (2 record(s) found.)
- Management Plans (1 record(s) found.)
- Orders (3 record(s) found.)
- COSEWIC Annual Reports (1 record(s) found.)
- Consultation Documents (2 record(s) found.)
COSEWIC Status Reports
Response Statement - Cryptic Paw Lichen (2020) (2020-01-07)COVID-19 and the consultations on the listing of species at risk As a result of the ongoing COVID 19 situation, it is not possible to have in-person meetings. Taking this into consideration, please note that consultation closing dates have been set for both the Normal and Extended consultations for the terrestrial species considered in this document. We will work to ensure that all the known, potentially affected parties have the opportunity to contribute to the consultations and that the consultation process is flexible and sensitive to the current context. If you wish to contribute, please submit your comments by April 2, 2021 for species undergoing normal consultations and by September 2, 2021 for species undergoing extended consultations. You may provide comments by email, letters, or through the online survey. This leafy lichen is endemic to western North America. In Canada the total estimated population is approximately 12,000 individuals. The species has specific habitat requirements, growing in humid old coastal and interior cedar-hemlock forests that have depressions kept moist by input from groundwater. The lichen reproduces only by vegetative propagules with limited capability for dispersal. The species is threatened by habitat loss as a result of forest harvesting, and by climate change leading to altered patterns of winter precipitation and warmer drier summers that can enhance the frequency and severity of fires. The IUCN Threats assessment calculator result for this species was Very High to High.
Response Statements - Cryptic Paw (2006-11-29)This foliose lichen is endemic to western North America where it is known in Canada from 45 locations, however there are likely more undiscovered locations. The Canadian sites account for more than 50% of the global range with only 5 locations protected from forest harvesting. The species has restricted habitat requirements and grows in mid to lower canopy of old growth coastal and interior humid cedar-hemlock forest. It reproduces only by vegetative propagules with limited dispersal distance. The species is vulnerable to forest harvesting, changes in understory humidity, insect defoliation (hemlock looper), and fire.
COSEWIC Annual Reports
COSEWIC Annual Report - 2006 (2006-08-30)2006 Annual Report to the The Minister of the Environment and the Canadian Endangered Species Conservation Council (CESCC) from the Committee on the Status of Endangered Wildlife in Canada.