- Proposed
- Under Assessment
- Preliminary Assessed
- Assessed
- CRPublished
Hypotrachyna virginica (Hale) Hale
- Scientific name
- Hypotrachyna virginica
- Author
- (Hale) Hale
- Common names
- IUCN Specialist Group
Lichens- Kingdom
- Fungi
- Phylum
- Ascomycota
- Class
- Lecanoromycetes
- Order
- Lecanorales
- Family
- Parmeliaceae
- Assessment status
- Published
- Assessment date
- 2019-09-27
- IUCN Red List Category
- CR
- IUCN Red List Criteria
- A3c
- Assessors
- James Lendemer (Institute of Systematic Botany The New York Botanical Garden); Troy McMullin (Biodiversity Institute of Ontario Herbarium, University of Guelph); Jessica Allen (IUCN SSC Lichen Specialist Group)
- Reviewers
- Rebecca Yahr
Assessment Notes
Justification
Hypotrachyna virginica warrants a status of critically endangered as its AOO and EOO are projected to reduce by >80% within its next three generations. Species distribution models projected to 2050 and 2070 using two different climate change models (CCSM4 and HadGEM2-AO) at the lowest and highest carbon dioxide concentration (2.6 and 8.5 rcp) were recently built in Maxent for this species (Allen and Lendemer, 2016). The results of the modeling predict an average suitable habitat loss of 94.3% with a minimum loss of 83.4% and a maximum loss of 100%. This represents a significant decrease in the AOO and EOO for the species.Geographic range
This species is narrowly endemic to high-elevations in the southern Appalachian Mountains of eastern North America where it grows predominantly in spruce-fir forests. It was first described from Hawksbill Mountain in Virginia and was subsequently found at high-elevations on Mount Rogers, Roan Mountain, the Black Mountains, the Balsam Mountains, the Plott Balsam Mountains and the Great Smoky Mountains. Confusion around the presence of this species in the Caribbean and Mexico was recently clarified as specimens collected outside of the southern Appalachian Mountains were determined to be other species of Hypotrachyna (Lendemer and Allen 2015).Population and Trends
There is a total of 10 extant locations and seven locations that are presumed extirpated based on recent surveys. Detailed historical distribution data exist for this species from Jon Dey's dissertation on high-elevation macrolichens in the southern Appalachians (Dey 1978). Most of the locations and areas visited by Dey have been revisited in recent years by J.L. Allen, J.C. Lendemer, E. Tripp and R.C. Harris. The locations in the Black Mountains (3 locations) and Roan Mountain (1 location) have recently been relocated and are still extant. In the Balsam Mountains two historical locations could not be relocated, but one new location was documented, for a total of one extant location. The occurrences on Mount Rogers were also relocated recently (2 locations). One location each in Great Smoky Mountains National Park and the Plott Balsam Mountains have not been found again. However, two additional occurrences have recently been documented from the Great Smoky Mountains. Recent surveys of the original locality at Hawksbill Mountain by multiple specialists did not relocate any individuals.
Population Trend: Stable
Habitat and Ecology
This species grows predominantly in spruce-fir forests, a critically imperilled ecosystem (G1-G2 ranking, White et al. 2012), and occasionally on heath balds. It grows on both hardwood and coniferous trees, and reproduces almost exclusively through vegetative reproduction and is not well suited to long distance dispersal.
Threats
Major threats to this species include the loss of mature, healthy spruce-fir forest due to the balsam wooly adelgid decimating large stands of Abies fraseri (Rose and Nicholas 2008, Rollins et al. 2010, White et al. 2012). Any logging activity or other land use change would also result in major losses of populations of this species. Species distribution models projected to 2050 and 2070 using two different climate change models (CCSM4 and HadGEM2-AO) at the lowest and highest carbon dioxide concentration (2.6 and 8.5 rcp) were recently built in Maxent for this species (Allen and Lendemer, 2016). Acid rain is another major threat to this species.
Conservation Actions
Three main actions will help ensure the continued survival of this species: 1) global reduction of greenhouse gas emissions, 2) protection from logging and other land-use changes near all locations, and 3) research investigating the potential to transplant this species for reintroduction and/or assisted migration.
