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Elgaria panamintina
– Vulnerable
Taxonomy
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Kingdom:
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ANIMALIA
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Phylum:
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CHORDATA
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Class:
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REPTILIA
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Order:
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SQUAMATA
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Family:
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ANGUIDAE
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Scientific Name:
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Elgaria panamintina
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Species Authority:
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(Stebbins, 1958)
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Synonym/s:
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Gerrhonotus panamintus Stebbins, 1958
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Common Name/s:
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PANAMINT ALLIGATOR LIZARD (Eng)
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Taxonomic Notes:
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Elgaria panamintina was formerly included in the genus Gerrhonotus (see Good 1988).
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Assessment Information
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Red List Category & Criteria:
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VU B1ab(iii); C2a(i) ver 3.1 (2001)
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Year Assessed:
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2007
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Assessor/s:
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Hammerson, G.A.
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Evaluator/s:
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Cox, N., Chanson, J.S. & Stuart, S.N. (Global Reptile Assessment Coordinating Team)
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Justification:
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Listed as Vulnerable because its extent of occurrence is less than 20,000 km², its distribution is severely fragmented, and there is probably continuing decline in the extent and quality of its habitat; and because the population size is estimated to number fewer than 10,000 mature individuals, and is probably experiencing a continuing decline, and no subpopulation is estimated to contain more than 1,000 mature individuals.
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History:
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| 1986 | - | Insufficiently Known as Gerrhonotus panamintus (IUCN Conservation Monitoring Centre 1986) |
| 1988 | - | Insufficiently Known as Gerrhonotus panamintus (IUCN Conservation Monitoring Centre 1988) |
| 1990 | - | Insufficiently Known as Gerrhontus panamintinus (IUCN 1990) |
| 1994 | - | Insufficiently Known as Gerrhonotus panamintus (Groombridge 1994) |
| 1996 | - | Vulnerable as Gerrhonotus panamintus (Baillie and Groombridge 1996) |
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Geographic Range
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Range Description:
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This species is known only from California in the United States. It is known several locations in desert mountains of Inyo and Mono counties, east-central California (Stebbins 2003). Some specific locations include the following: Panamint Mountains (Brewery and Limekiln springs, Surprise Canyon, Pleasant Canyon, Wildrose Canyon, middle fork of Hanaupah Canyon), Nelson Mountains (Grapevine Canyon), Inyo Mountains (Daisy Canyon, Lime Hill, Long John Canyon, French Spring), White Mountains (Batchelder Spring, Westgard Pass, Marble Canyon, Tollhouse Spring, Black Canyon, Cottonwood Canyon, Silver Creek Canyon, Coldwater Creek, above Chalfant and Hammil valleys), eastern Argus Mountains, Cosos Mountains (Banta et al. 1996). Its occurrence in talus habitat suggested to Banta et al. (1996) that the geographic range may be broader than is now known. However, the known area of occupancy is very small (probably less than 5 sq. km if one assumes that each occupied patch is 2 km long and 0.1 km wide). Elevational range is about 2,500 to 7,500 feet (760 to 2,300 m).
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Range Map:
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 (click for detailed map)
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Countries:
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Native:
United States (California)
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Population
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Population:
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Only 24 museum specimens from 16 localities and an additional 11 sight records have accumulated since the species was described in 1958 (Banta et al. 1996). Banta et al. (1996) mapped 23 locations. The total adult population size of this secretive and apparently rare lizard is unknown, but probably it is at least 1,000 (assuming at least 20 subpopulations of 50 or more adults). Population trends cannot be determined with certainty, but the extent of occurrence and area of occupancy have probably been relatively stable over the long term. Abundance probably has declined in some areas where the habitat has been degraded.
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Population Trend:
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Habitat and Ecology
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Habitat and Ecology:
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This lizard occurs in regions dominated by scrub desert, Joshua tree woodland, and the lower edge of the pinyon-juniper belt (Stebbins 1985). Most known locations are in canyon riparian zones below permanent springs; but individuals may range into talus slopes some distance from the immediate riparian zone (Good 1988, Jennings and Hayes 1994, Banta et al. 1996). Individuals have been found under willow thickets along watercourses, under shrubs in drier areas, and in rock slides. When inactive, the lizards hide underground, under stones or wood, or in crevices. Habitats in order of decreasing favourability: (1) along creeks with riparian vegetation, (2) along small springs with riparian vegetation, (3) near small springs in pinyon-juniper or Joshua tree woodland, (4) pinyon juniper and Joshua tree woodland in canyons or washes. Occupied riparian zones are typically only a few metres wide and less than three km long (Jennings and Hayes 1994).
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System:
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Terrestrial; Freshwater; Marine
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List of Habitats:
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| 1.4 | Forest - Temperate |
| 5.9 | Wetlands (inland) - Freshwater Springs and Oases |
| 6 | Rocky areas (eg. inland cliffs, mountain peaks) |
| 8.2 | Desert - Temperate |
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Threats
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Threats:
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According to Jennings and Hayes (1994), all but a few of the known populations occur on private lands and are currently at risk from mining, feral and domestic livestock grazing, and increasing off-road vehicle activity.
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List of Threats:
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| 1.1.4.3 | Habitat Loss/Degradation - Agriculture - Livestock - Agro-industry (ongoing) |
| 1.3.1 | Habitat Loss/Degradation - Extraction - Mining (ongoing) |
| 10.1 | Human disturbance - Recreation/tourism (ongoing) |
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Conservation Actions
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Conservation Actions:
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Enhanced protection of riparian zones in desert canyons would benefit this species. It appears not to be known from any protected areas, though it might occur in some.
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List of Conservation Actions:
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| 0 | No conservation actions (in place, needed) |
| 3.2 | Research actions - Population numbers and range (in place, needed) |
| 3.3 | Research actions - Biology and Ecology (in place, needed) |
| 3.4 | Research actions - Habitat status (in place, needed) |
| 3.5 | Research actions - Threats (in place, needed) |
| 3.8 | Research actions - Conservation measures (in place, needed) |
| 3.9 | Research actions - Trends/Monitoring (in place, needed) |
| 4.1 | Habitat and site-based actions - Maintenance/Conservation (in place, needed) |
| 4.2 | Habitat and site-based actions - Restoration (in place, needed) |
| 4.4.1 | Habitat and site-based actions - Protected areas - Identification of new protected areas (in place, needed) |
| 4.4.2 | Habitat and site-based actions - Protected areas - Establishment (in place, needed) |
| 4.4.3 | Habitat and site-based actions - Protected areas - Management (in place, needed) |
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Bibliography
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Bibliography:
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Baillie, J. and Groombridge, B. (compilers and editors) 1996. 1996 IUCN Red List of Threatened Animals. IUCN, Gland, Switzerland. Banta, B.H., Mahrdt, C.R. and Beaman, K.R. 1996. Elgaria panamintina. Catalogue of American Amphibians and Reptiles 629: 1-4. Good, D.A. 1988. Allozyme variation and phylogenetic relationships among species of Elgaria (Squamata: Anguidae). Herpetologica 44: 154-162. Good, D.A. 1988. Phylogenetic relationships among gerrhonotine lizards: an analysis of external morphology. University of California Publications in Zoology 121: 1-139. Groombridge, B. (ed.) 1994. 1994 IUCN Red List of Threatened Animals. IUCN, Gland, Switzerland. IUCN Conservation Monitoring Centre. 1986. 1986 IUCN Red List of Threatened Animals. IUCN, Gland, Switzerland and Cambridge, UK. IUCN Conservation Monitoring Centre. 1988. 1988 IUCN Red List of Threatened Animals. IUCN, Gland, Switzerland and Cambridge, UK. IUCN. 1990. 1990 IUCN Red List of Threatened Animals. IUCN, Gland, Switzerland and Cambridge, UK. Jennings, M.R. and Hayes, M.P. 1994. Amphibian and reptile species of special concern in California. Final Report submitted to the California Department of Fish and Game, Inland Fisheries Division, Rancho Cordova. Contract No. 8023. 255 pp. Stebbins, R.C. 1985. A Field Guide to Western Reptiles and Amphibians. Second Edition. Houghton Mifflin Company, Boston, Massachusetts. Stebbins, R.C. 2003. A Field Guide to Western Reptiles and Amphibians. Third Edition. Houghton Mifflin Company, Boston, Massachusetts.
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