The alpine salamander (Salamandra atra) is a black salamander that can be found in the Alps, and through the mountainous range in Europe. It is a member of the genus Salamandra. Their species name, atra, may be derived from the Latin ater, meaning dull black. The salamanders' coloration has evolved over time, as some species are completely monochrome black and others have yellow spotting and marks. Unlike other salamanders, whose larvae are developed in water, the alpine salamander and its subspecies are a fully terrestrial species in life and gestation. The salamanders have parotid glands posterior and lateral to their eyes, giving them an elongated head shape. Scientists have studied the hypothesis of if the salamanders start completely black, or if they evolved like that over time. DNA-evidence traced through maternal lineages suggest the latter: that salamanders evolved their black coloration over time. In S. atra, there are different cells present or activated, which yield different colors: melanophores contribute to the dark coloration by producing the dark pigment melanin, The pure black coloring is also hypothesized to be a form of thermoregulation,
- S. a. pasubiensis, with fewer yellow spots than S. a. aurorae, lives in a different part of the Venetian Prealps.
- S. a. prenjensis lives on Prenj Mountain, part of the Dinaric Alps in Bosnia and Herzegovina. The validity of this subspecies is yet to be confirmed, and some scientists in the field debate if this salamander should be considered its own independent species.
Genetic analysis suggests that the Corsican fire salamander (Salamandra corsica) is the closest related species, and the black-yellow coloration is an ancestral feature of alpine salamanders. Proposed colonization from south (Prealps) to Alps was carried out by the fully melanistic (derived feature) S. a. atra after the last retreat of the ice sheets. S. atra tend to live underneath stones or logs, or in rocky crevices in their mountainous habitat. Ideal weather for alpine salamanders is rainy or post-rain, at temperatures between .
Their range spans several nations, including: Slovenia, Croatia, Bosnia, Hersegovina, Montenegro, Kosovo, France, Italy, Austria, Algeria, Switzerland.
Home range and territoriality
thumb|Alpine salamanders in leafy terrain
thumb|A salamander in Slovenia
They thrive in forest environments that have silver fir and beech trees. Coniferous forests that have high proportions of Norway spruce and European larch trees also provide adequate habitats, even though the salamanders live on the ground floor. was the maximum observed distance traveled by one individual during the summer season. About 120 individuals per hectare were counted in most suitable areas with over 2000 individuals per hectare also observed, suggesting that this rather cryptic species is quite abundant. Alpine salamanders can determine if a found fecal pellet has been left by a member of their same sex and/or species. Population numbers are declining in S. a. aurorae, for example.
One of the greatest dangers to alpine salamanders overall is commercial deforestation in their habitats. Amphibians and other organisms that do not internally regulate their body temperature may need adaption mechanisms to remain at ideal physiological temperatures in the face of changing climates. There are already animal and ecosystem conservation laws in Europe, but many scholars recommend additional ones to protect the flora and fauna.
Predators
Due to their toxicity, researchers are unsure of consistent predators for alpine salamanders with limited observation. Some specific organisms they prey on include species such as beetles, snails, millipedes, and spiders, but alpine salamanders display preferences among prey. Oftentimes, one male will mount the other, loosely grasp it with his forearms, and start rubbing his head on the other male. Mating occurs on land. The male clasps the female at the forelegs, and fertilization is internal. S. atra are categorized as viviparous, meaning that their young are born alive and unlike many other amphibians, do not go through metamorphosis The uterine eggs are large and numerous, but, as a rule, only one fully develops in each uterus. The embryo is nourished on the yolk of the other eggs, which more or less dissolve to form a large mass of nutrient matter. The egg mass can be as long as 25 - 40 mm.
- The first stage is when they are still enclosed within the egg and living on its own yolk. They are neurotoxins, and are synthesized via a biochemical pathway, completely independent of dietary intake. Salamandorone is another biochemical compound produced by S. atra, and though it is less potent against prey it is the strongest antimicrobial weapon these salamanders have. This dangerous fungal infection, caused by Batrachochytrium dendrobatidis (Bd) has decimated amphibian populations on every continent. This theory is untested, but considering how many salamanders excrete biological toxins, plausible.