Description
provided by AmphibiaWeb articles
A small terrestrial salamander. Stocky with relatively long legs, adults range in size from 4.5 to 5.8 cm snout to vent length (9.5-10.5 cm total length). Modal number of costal grooves is 14. Males are slightly smaller than females and have a mental gland, a raised area on the chin used in courthip. There are indistinct paratoid glands on the back of the head, and the feet are broad and slightly webbed (Brodie and Storm 1970; Petranka 1998). Hatchlings are 15-18 mm snout to vent length (Nussbaum et al. 1983).Three color morphs occur and populations often have 2 or, rarely, all 3. The dark phase is dark brown to black dorsally with a yellow,orange, green, or red stripe that extends to the tip of the tail. The venter is dark and the throat is yellow. The yellow morph has a tan or yellowish ground color dorsally and ventrally, and the rosemorph is similar with a pinkish to salmon coloration over the body (Brodie 1970; Nussbaum et al. 1983).Plethodon idahoensis was formerly included within P. vandykei, sometimes treated as a subspecies, but mitochondrial data reveal deep divergence between the two (Carstens et al. 2004). Genetic work throughout the range of these forms has supported suggestions that populations in the Rocky Mountains be regarded as a separate species from populations in western Washington (Highton and Larson 1979; Collins 1991; Howard et al. 1993).
- Blessing, B.J., Phenix, E.P., Jones, L. and Raphael, M.G. (1999). ''Nests of the Van Dyke's salamander (Plethodon vandykei) from the Olympic Peninsula, Washington.'' Northwestern Naturalist, 80, 77-81.
- Brodie, E. D., Jr., and Storm, R. M. (1970). ''Plethodon vandykei Van Denburgh. Van Dyke's Salamander.'' Catalogue of American Amphibians and Reptiles. American Society of Ichthyologists and Herpetologists, 91.1-91.2.
- Carstens, B. C., Stevenson, A. L., Degenhardt, J. D., and Sullivan, J. (2004). ''Testing nested phylogenetic and phylogeographic hypotheses in the Plethodon vandykei species group.'' Systematic Biology, 53, 781-792.
- Hammerson, G. 2004. Plethodon vandykei. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4. www.iucnredlist.org. Downloaded on 13 March 2011.
- Jones, L. L. C. (1989). ''Plethodon vandykei (Van Dyke's Salamander). Reproduction.'' Herpetological Review, 20, 48.
- Lynch, J. E., Jr., and Wallace, R. L. (1987). ''Field observations of courtship behavior in Rocky Mountain populations of Van Dyke's Salamander, Plethodon vandykei, with a description of its spermatophore.'' Journal of Herpetology, 21, 337-340.
- McIntyre, A. P., Schmitz, R.A., and Crisafulli, C.M. (2006). ''Associations of the Van Dyke’s Salamander (Plethodon vandykei) with geomorphic conditions in Headwall Seeps of the Cascade Range, Washington State.'' Journal of Herpetology, 40, 309-322.
- Welch, H. H., Jr. (1990). "Relictual amphibians and old-growth forests." Conservation Biology, 4, 309-319.
- author
- Meredith J. Mahoney
Distribution and Habitat
provided by AmphibiaWeb articles
This species has a patchy distribution in western Washington with populations in the Willapa Hills, the Olympic peninsula and Mt. St. Helens/Mt. Rainier in the Cascade range. Preferred habitats are conifer forests with average annual rainfall >150 cm. The most aquatic species of Plethodon, animals are frequently found in seepages and splash zones of waterfalls and in rocky areas along streams (Brodie 1970). Populations may also be associated with talus, and away from streams individuals can be found under an assortment of cover objects (Nussbaum et al. 1983; Petranka 1998).
- author
- Meredith J. Mahoney
Life History, Abundance, Activity, and Special Behaviors
provided by AmphibiaWeb articles
Like other members of the genus Plethodon, P. vandykei is completely terrestrial through all stages of its life history; courtship, mating, and egg deposition occur on land. There is no free living larval stage, and juveniles hatch completely metamorphosed (Stebbins 1985; Petranka 1998). Courtship behavior has not been described in detail for this species, butis probably similar to the closely related species P. idahoensis. Fertilization occurs by means of a spermatophore deposited on the substrate by the male and picked up in the cloaca by the female (Lynch and Wallace 1987). Courtship occurs in spring and perhaps fall. Oviposition takes place in the spring. Females attend the eggs until hatching in the fall (Nussbaum et al. 1983; Jones 1989). Clutch size ranges from 7-14 (Stebbins 1951; Jones 1989). Eggs are cream-colored and measure about 4-5 mm in diameter (Blessing et al. 1999). Each clutch is suspended by one or two gelatinous threads attached to the walls of the cavity (Blessing et al. 1999).Only six nests of Van Dyke's salamanders have been discovered. The first was described as a "grape-like cluster" attached by a common pedicel to a moss-covered stone in a damp location (Noble 1925) and the second was located inside a partially rotted log (85 cm in diameter and 5 m in length) in an old-growth forest on a north-northeast facing slope, near a small headwater stream (Jones 1989). Four additional nests were found in logs near undisturbed or protected streams during the summer of 1997, in the Olympic Peninsula (Blessing et al. 1999). Three of those four nests were located in old-growth forest (western hemlock and Pacific silver fir), while one was located inside a buffer of old trees in a clear-cut area. The four clutches were all found in cavities in sapwood, 6.5-7.0 cm below the surface of large decaying moss-covered conifer logs, and were each attended by an adult salamander (likely female). Clutches were left in the logs and took 144 days of observation to hatch, a much longer period than reported for other species of Plethodon (generally about 45-90 days, according to Petranka 1998).Not much is known about the natural history of this species. Adults are most active in the spring and fall months, but individuals are not commonly encountered (Petranka 1998).
- author
- Meredith J. Mahoney
Life History, Abundance, Activity, and Special Behaviors
provided by AmphibiaWeb articles
Patchy distribution and apparently low population densities suggest that this species should receive conservation attention. Populations are at risk from logging and intense management of forests (Welsh 1990; Petranka 1998). This species has limited ability to survive in disturbed habitat (Hammerson 2004). It occurs in two protected areas, Mt. St. Helens National Monument and Olympic National Park (Hammerson 2004).
- author
- Meredith J. Mahoney
Van Dyke's salamander
provided by wikipedia EN
Van Dyke's salamander (Plethodon vandykei) is a small woodland salamander in the family Plethodontidae, the lungless salamanders. These animals breathe through their skin and are largely terrestrial. Compared to other salamanders in Plethodon it is relatively stocky with long legs. Usually associated with streams, seepages, and rock outcrops, it is endemic to Washington where it is found in a limited number of small, isolated populations.
Taxonomy
Van Dyke's salamander was first described by John Van Denburgh in 1906 from a specimen found in Mount Rainier National Park. The species was named in honor of its collector, Edwin Cooper Van Dyke. The Coeur d'Alene salamander (Plethodon idahoensis) and the Larch Mountain salamander (Plethodon larselli) are its two closest relatives in the region. At one time, all three were thought to be members of the same species until genetic studies concluded that they were distinct species.[2][3]
Description
Van Dyke's salamander has a relatively stocky body and grows up to 10 cm long. There are parotoid glands behind the eyes, and the feet are broad and slightly webbed. Different color phases are described based on body color, which can be black, yellow, or pink. The "dark phase" has a black ground color and yellow or red dorsal stripe. The stripe appears to have drops of color extending down the sides. The "light phase" is tan, yellow or rose with an indistinct stripe.[2] Dark phase individuals have white speckling on the sides and a yellow throat. Multiple color phases can occur within the same population.
They are completely terrestrial but require high soil moisture and cool temperatures. They are most active in the spring after snow-melt and in the fall after the onset of the rainy season. They avoid the summer heat and the freezing temperatures of winter, seeking shelter beneath stones or within rotting logs. Courtship and egg laying occurs in the spring. Clutch size ranges from 7-14 eggs which measure about 4–5 mm in diameter. Females attend the eggs until hatching in the fall. There is no larval stage; hatchlings emerge as juvenile salamanders.[4]
Distribution and habitat
Van Dyke's salamander is endemic to the western portion of Washington. It occurs in three disjunct areas: on the Olympic Peninsula, in the Willapa Hills, and in the southern Cascade Range. They generally occur in small isolated populations that are usually associated with streams, seepages, and rock outcrops. Van Dyke's Salamander is absent from the eastern slopes of the Cascade Range and Olympic Range, suggesting this salamander's association with high rainfall regions. In coastal areas, it is mostly found in old forest stands that have moderate to high levels of woody debris and fractured rock present. Large decaying conifer logs along streams appear to be important habitat for nesting.[4]
Conservation
Threats to the Van Dyke's salamander are not well studied, but patchy distribution and low population densities would indicate that this species should receive conservation attention. Populations are at risk from logging, road construction, and other activities that could impact or degrade their specific habitat requirements. Surveys suggest that this species has limited ability to survive in disturbed habitat.[5] It occurs in two protected areas, Mount St. Helens National Volcanic Monument and Olympic National Park.[2][4]
Notes
References
- license
- cc-by-sa-3.0
- copyright
- Wikipedia authors and editors
Van Dyke's salamander: Brief Summary
provided by wikipedia EN
Van Dyke's salamander (Plethodon vandykei) is a small woodland salamander in the family Plethodontidae, the lungless salamanders. These animals breathe through their skin and are largely terrestrial. Compared to other salamanders in Plethodon it is relatively stocky with long legs. Usually associated with streams, seepages, and rock outcrops, it is endemic to Washington where it is found in a limited number of small, isolated populations.
- license
- cc-by-sa-3.0
- copyright
- Wikipedia authors and editors
