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An adult salamander generally resembles a small lizard, having a basal tetrapod body form with a cylindrical trunk, four limbs, and a long tail. Except in the family Salamandridae, the head, body, and tail have a number of vertical depressions in the surface which run from the mid-dorsal region to the ventral area and are known as costal ...
Sirenidae, the sirens, are a family of neotenic aquatic salamanders. Family members have very small fore limbs and lack hind limbs altogether. [1] In one species, the skeleton in their fore limbs is made of only cartilage. In contrast to most other salamanders, they have external gills bunched together on the neck in both larval and adult states.
The Salamandroidea are a suborder of salamanders, referred to as advanced salamanders.The members of the suborder are found worldwide except for Antarctica, sub-Saharan Africa, and Oceania.
The origins and evolutionary relationships between the three main groups of amphibians (apodans, urodeles and anurans) is a matter of debate.A 2005 molecular phylogeny, based on rDNA analysis, suggested that the first divergence between these three groups took place soon after they had branched from the lobe-finned fish in the Devonian (around 360 million years ago), and before the breakup of ...
There are seven main taxonomic ranks: kingdom, phylum or division, class, order, family, genus, and species. In addition, domain (proposed by Carl Woese ) is now widely used as a fundamental rank, although it is not mentioned in any of the nomenclature codes, and is a synonym for dominion ( Latin : dominium ), introduced by Moore in 1974.
Authorities disagree as to whether Salientia is a superorder that includes the order Anura, or whether Anura is a sub-order of the order Salientia. The Lissamphibia are traditionally divided into three orders , but an extinct salamander-like family, the Albanerpetontidae, is now considered part of Lissamphibia alongside the superorder Salientia.
The family Plethodontidae consists of two extant subfamilies and about 516 [2] to 520 [1] species divided among 29 genera, making up the majority of known salamander species: [2] Subfamily Genus, scientific name, and author
The genus Rhyacotriton was formerly included in this family, but is now usually placed into its own family Rhyacotritonidae. In 2006, a large study of amphibian systematics (Frost et al., Bulletin of the American Museum of Natural History, 297 (2006) placed Dicamptodon back within Ambystomatidae, based on cladistic analysis. This has been ...