Editing Palmate newt (section)

==Description==

[[File:Fadenmolch_(Lissotriton_helveticus),_Fagne_de_la_Petite_Roer,_Sourbodt,_Ostbelgien_(48972546703).jpg|thumb|alt=Brown, rouhg-skinned newt on leave litter|Male during land phase, with dry, velvety skin]]

[[File:Triton_Palmé_Lissotriton_helveticus.jpg|thumb|alt=Newt held between two fingers, exposing its yellow underside|The underside is yellow to orange, and the throat always unspotted.]]

[[File:Triturus.helveticus.jpg|thumb|alt=Newt under water, holding on to plant|Breeding male with angular body, low smooth crest, tail filament and webbed hind feet]]

[[File:Fadenmolchweibchen.jpg|thumb|alt=Newt under water seen from side|Breeding female with orange strip on tail but without tail filament]]

Palmate newts grow to about {{convert|5–8.5|cm|in|abbr=on}} total length in males, while females are somewhat larger and can reach {{convert|9.5|cm|in|abbr=on}}. The tail is slightly shorter than the [[snout-vent length|snout–vent distance]]. The head is longer than wide, with three longitudinal grooves on the snout. Both sexes have an olive or brown base colour, and males and some females have dark spotting on their backs. In females, the spots can sometimes form two irregular lines, and they can have a red stripe running along the back while living on land. In both sexes, a dark stripe runs along the head through the eyes. The underside is yellow or light orange and more whitish on the sides; the belly can have some dark spots, while the throat is always unspotted. While the newts live on land, the skin is dry and velvety, but it becomes smooth when they [[migration (ecology)|migrate]] into water.{{r|1=VanderMeijden2000|2=Sparreboom2014|p2=224–225}}

Males can be distinguished from females by the larger and darker-coloured [[cloaca]].{{r|VanderMeijden2000}} During the aquatic breeding season, the cloaca swells, and other sexual differences develop: Males grow a low, smooth skin seam (a crest) on their back, which is higher on the tail. Their tail has a blunt end with a distinct, 4–7&nbsp;mm long filament. They also have ridges (dorso-lateral ridges) running along their sides, giving them an angular, square shape in cross-section, and their hind feet have well-developed, dark webbing. The lower half of the tail is blue in breeding males and orange in females. Development of the crest, tail filament, ridges, and webbing can be suppressed in the presence of the newts' natural predators. When exposed to predatory [[goldfish]], newts do not express these traits, as large sexual ornaments would make them more conspicuous prey.<ref>{{Cite journal |last1=Winandy |first1=L. |last2=Denoël |first2=M. |date=May 2015 |title=Expression of sexual ornaments in a polymorphic species: phenotypic variation in response to environmental risk |journal=Journal of Evolutionary Biology |language=en |volume=28 |issue=5 |pages=1049–1056 |doi=10.1111/jeb.12636|pmid=25847588 |s2cid=18564451 |doi-access=free }}</ref> Females do not develop a crest, tail filament or webbed feet.{{r|1=VanderMeijden2000|2=Sparreboom2014|p2=224}}

Sometimes confused with the [[smooth newt]] (''Lissotriton vulgaris'') which is found in much of the same area, the palmate newt can be distinguished by its unspotted throat.{{r|VanderMeijden2000}} It also resembles [[Bosca's newt|Boscá's newt]] (''L. boscai'') from the Iberian peninsula, which has only a single groove on the snout and no dark eye strip.{{r|Sparreboom2014|p=222}}