Breeding males develop a distinct filament on the end of their tail, strongly webbed hind feet, and a low, smooth crest on their back.

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.

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.

[11] 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.

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.

[11] It also resembles Boscá's newt (L. boscai) from the Iberian peninsula, which has only a single groove on the snout and no dark eye strip.

[4]: 222 The palmate newt occurs in Western Europe, from Great Britain (up to Scotland) to northern Portugal and Spain.

[11][4]: 224  Genetic analyses by Recuero and García-París suggest that the species was confined to the Iberian Peninsula during the Last Glacial Maximum and then expanded its range north of the Pyrenees.

[14] Common over most of its range, the palmate newt is found in a variety of habitats, including forest, marshes and pasture.

[1][10] For reproduction, the newts accept different types of stagnant water bodies, preferably fish-free; acidic ponds are well tolerated.

[4] The reproductive period usually extends from February to May, but can start earlier or last longer in the southern range on the Iberian Peninsula, depending on elevation.

[11] Breeding involves a ritualised courtship display as in other closely related newts: The male attempts to attract a female by swimming in front of her and sniffing her cloaca.

[1] In France, it is the most common newt species,[10] but it is rare in Belgium and the Netherlands,[4]: 225  and populations are fragmented on the Iberian peninsula.

[1] Drainage and pollution of breeding sites, the introduction of fish and crayfish, as well as desertification (in the southern range), have been cited as threats.