Calotriton and Triturus are estimated to have split approximately 8 myr ago. This may have been associated with adaptation to fast-running, well-oxygenated mountain streams (instead of ponds in Triturus), leading to some superficial similarity with Euproctus in convergent evolution: strongly depressed head and body, and reduction or even absence of lungs.[3]
Description
Calotriton are small- to medium-sized newts, 70–167 mm (2.8–6.6 in) in total length. Skin is covered with tubercles bearing horny tips, more so above than beneath, which can be completely smooth. Limbs are moderate, with four fingers and five toes. Body is rounded or slightly depressed. There is no cutaneous dorsal and caudal crest, not even during the breeding season. Tail is about as long as head and body and compressed from side; longer in females and deeper in males. Lungs are absent or very reduced.[3]
^ abFrost, Darrel R. (2014). "Calotriton Gray, 1858". Amphibian Species of the World: an Online Reference. Version 6.0. American Museum of Natural History. Retrieved 9 March 2015.
^"Salamandridae". AmphibiaWeb: Information on amphibian biology and conservation. [web application]. Berkeley, California: AmphibiaWeb. 2015. Archived from the original on 15 April 2019. Retrieved 9 March 2015.
Andreas Nöllert & Christel Nöllert: Die Amphibien Europas. – Franckh-Kosmos, Stuttgart, 1992. ISBN3-440-06340-2