Streamside Salamander (Ambystoma barbouri)
Description: The streamside salamander is a medium-sized amystomatid salamander. It typically has a relatively small head and a short rounded snout. The salamander's body is relatively short and flaccid. There are 14 to 15 distinct costal grooves when fully grown. The tail is fairly short and thick, and it contains costal grooves that correspond directly to the vertebrae. Coloring is typically a dark black background covered in lichen-like markings in gray and brown. The species has more teeth, with a unique cusp shape, in its maxillary and premaxillary positions than its close relatives teeth, and is somewhat stockier.
Habitat: Adults can be found underground and under rocks or leaves in deciduous forests at moderate elevations. The streamside salamander is closely related to the pond-breeding small-mouth salamander, from which it is believed to have diverged during the late Pleistocene era as a result of climatic warming. Disappearance of pond habitats are thought to have forced the species to adapt to the new stream habitat.
Range: The species is found in central Kentucky, southwestern Ohio, southeastern Indiana. There is an isolated population in Livingston County, Kentucky. Overall distribution is uncertain due to the species' cryptic habits and possible confusion or hybridization with the small-mouth salamander.
Diet: One study analyzing the gut contents of larvae showed macrozooplankton and chironimid larvae in high abundance, as well as amphipod and isopods as high-volume prey. Larvae have also been shown to consume large numbers of isopods in a separate study.
Reproduction: Breeding season begins with migratory movement of adult salamanders to stream breeding sites from late October into early March. The beginning of migration is strongly correlated with rainfall. Males usually migrate toward the breeding sites before females.
Ambystoma barbouri eggs are internally fertilized via spermatophores deposited by males on the submerged underside of flat, streambed rocks. Males begin courtship by dramatically undulating their tail while swimming around the shallow stream underneath cover rocks. They do this while occasionally nudging the female, and then deposit spermatophores to the submerged rock. Females pick up the spermatophores from the submerged rock surface, and it is under these refugia that other courtship behaviors are thought to occur. After fertilization, females deposit their eggs onto the submerged rock surface in monolayers.
Status: Listed as Near Threatened because its Extent of Occurrence is probably not much greater than 20,000 km2, and the extent and quality of its habitat are probably declining, thus making the species close to qualifying for Vulnerable.
»» Kingdom: Animalia - Animals
»» Phylum: Chordata - Chordates
»» Subphylum: Vertebrata - Vertebrates
»» Class: Amphibia - (Amphibians)
»» Order: Caudata - Salamanders
»» Family: Salamandridae - Newts
»» Subfamily: Pleurodelinae - Pleurodeline Newts
»» Genus: Ambystoma
»» Species: Ambystoma barbouri - Streamside Salamander
This article uses material from the Wikipedia article "Streamside Salamander", which is released under the Creative Commons Attribution-Share-Alike License 3.0. Content may have been omitted from the original, but no content has been changed or extended.
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