Desert worm salamander
| Desert worm salamander | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Batrachoseps major aridus | ||||||||||||
| Brame , 1970 |
The desert worm salamander ( Batrachoseps major aridus , Syn .: Batrachoseps aridus ) is a rare subspecies of the California worm salamander that is endemic to southern California . It was discovered in 1970 and first described as an independent species, Batrachoseps aridus . After a phylogenetic analysis of the worm salamander by Elizabeth L. Jockusch , Kay P. Yanev and David B. Wake , it was classified as a subspecies in 2001.
features
The desert worm salamander has a body length of about 10.2 cm from the snout to the tip of the tail. It has four toes on each foot and a large, rounded head. The back is dark brown to deep chocolate brown with numerous small silvery-blue spots and speckled large gold-colored spots. The belly is dark brown and the tail is a contrasting flesh color.
distribution
There is little information about the historical distribution of the desert worm salamander. It has only been recorded on the lower slopes of the Santa Rosa Mountains in Riverside County in Southern California. Because of its isolation from other members of the genus and its primitive characteristics, the desert worm salamander is considered a relic form that was more common in earlier, wetter geological epochs.
habitat
The desert worm salamander is found in an arid region with low and irregular rainfall, high summer temperatures and strong spring winds. Above and below the limestone layers inhabited by the salamander there are seasonal watercourses between steep canyon walls made of igneous and metamorphic rock. The soil on the surrounding slopes consists of exposed bedrock, rubble and coarse-grained sand. The sparse flora is dominated by fan palms , Salix exigua , Baccharis sergiloides , Epipactis gigantea , lady ferns and Rhus ovata .
Way of life
The desert worm salamander is mostly found in porous soils, quarries or limestone slabs where the groundwater seeps through and provides moisture. Occasionally found under loose rocks during the day, this salamander is most active at night.
The diet of the desert worm salamander consists of small invertebrates, with flies and ants making up the majority. The influence of season, temperature, humidity, diet, prey capture and reproduction on the way of life and the population size of this subspecies is largely unexplored. Little is known about the breeding behavior of the salamander. Eggs are likely to be laid between November and January, shortly after the first heavy winter rain.
status
The greatest threat to this salamander's survival is its extremely limited range. This makes the desert worm salamander particularly vulnerable to any natural disaster. In 1976, for example, unusually heavy rainfall and flooding associated with a tropical storm caused the erosion and collapse of a limestone wall that made up up to a third of the salamander's habitat in Hidden Palms Canyon. Another extreme like a widespread drought could dry out the groundwater and lead to the extinction of this subspecies. There is little human activity in this area.
In June 1973, the desert worm salamander was included in the Endangered Species Act as a critically endangered species. In 1973, the State of California acquired 55 acres of land on which the Hidden Palms Ecological Reserve, administered by the California Fish and Game Commission, was established in 1974. After the 1976 floods, the rock wall of the habitat in Hidden Palms Canyon was reinforced to prevent further collapse. Rock barricades were erected to prevent unauthorized access to both gorges.
Originally, two populations were known from two locations about 4 miles apart, Hidden Palms Canyon and Guadalupe Canyon. Hidden Palms Canyon is located at the end of Deep Canyon, a large canyon that runs through the surrounding slopes of the Santa Rosa Mountains. The population in this area was estimated to be less than 500 individuals in the 1970s, but appears to have been extinct since 1996. The population of the Guadalupe Canyon has been little explored in terms of distribution and numbers.
literature
- Arden H. Brame, Jr .: A New Species of Batrachoseps (Slender Salamander) from the Desert of Southern California. Los Angeles County Museum Contributions to Science, No. 200, pp. 1-11, 1970
- Walton Beacham, Frank V. Castronova, Suzanne Sessine (Eds.): Beacham's Guide to the Endangered Species of North America. Volume 2 Amphibians, Fishes, Snails, Mussels and Clams, Gale Group, Farmington Hills, Michigan, 2001, ISBN 978-0-78765-033-9 , 2001, pp. 720-721
- US Fish and Wildlife Service: Desert slender salamander (Batrachoseps major aridus) 5-Year Review: Summary and Evaluation. US Fish and Wildlife Service, Carlsbad Fish and Wildlife Office Carlsbad, California, 2009
- Íñigo Martínez-Solano, Anny Peralta-García, Elizabeth L. Jockusch, David B. Wake, Ella Vázquez-Domínguez, Gabriela Parra-Olea: Molecular systematics of Batrachoseps (Caudata, Plethodontidae) in southern California and Baja California: Mitochondrial nuclear DNA discordance and the evolutionary history of B. major Molecular Phylogenetics and Evolution 63, 2012, pp. 131-149
Web links
- Californiaherps: Desert Slender Salamander - Batrachoseps major aridus
- The Ambiguous Extinction of the Desert Slender Salamander
- Entry on AmphibiaWeb
- Entry at Naturserve
Individual evidence
- ^ Arden H. Brame, Jr .: A New Species of Batrachoseps (Slender Salamander) from the Desert of Southern California. Los Angeles County Museum Contributions to Science No. 200, pp. 1-11, 1970
- ↑ Elizabeth L. Jockusch, Kay P. Yanev, David B. Wake: Molecular Phylogenetic Analysis of Slender Salamanders, Genus Batrachoseps (Amphibia: Plethodontidae), from Central Coastal California with Descriptions of Four New Species. Herpetological Monographs, Volume 15, 2001, pp. 54-99