Salamandra atra aurorae is a subspecies of the alpine salamander Salamandra atra found in south-eastern Italian Prealps. It is often called the golden alpine salamander.
Morphology Salamandra atra aurorae is very similar in body shape to all other subspecies of S. atra, also in all major characters that often distinguish different species of Salamandra: outline of the head, position of the vomerine teeth, proportions of body parts and limbs, arrangement of glandular bulges and pores on the skin, and shape and length of the tail. However, the body surface is not entirely and uniformly black as in most other populations of S. atra. Conversely, the dorsal side of S. atra aurorae is broadly covered with yellow blotches and brown spots, which are broader and often coalescent on the head and the trunk, they are usually present also on the arms, the thighs and the tail, whereas they are rare on the flanks and the ventral sides. Blotches are invariantly present in all individuals, but highly variable in extent (covering from slightly more than half of the dorsal surface to almost the entire dorsal surface) and in dominant hue (from pale yellow to marbled brown). The colour pattern is highly variable between individuals, without any obvious difference neither between sexes nor between sites. It is established at birth and it usually changes only slightly with growth. However, relatively rapid and extended changes from yellow to brown have been occasionally observed in captive individuals. Newly born individuals are about 50 mm long and less than 1 g, whereas adults may reach 134 mm in males and 139 mm in females, and 14 g in pregnant females. The sexual dimorphism is very slight, but it has not been investigated adequately. Like in other subspecies of S. atra, the cloacal region is usually swollen in the adult males.
Distribution Salamandra atra aurorae lives only in the northern part of the Sette Comuni plateau, in the Venetian Prealps, NE Italy. The actual distribution is known only incompletely, because the animals are very elusive and therefore hard to detect, and adequate investigations have not been carried out. As to 2016, all documented or reliable records cluster in 12 areas, more than 0.7 km far from each other and approximately aligned West to East from Val Postesina to Monte Fossetta. However, it is unknown whether the populations detected in these areas are actually separated or instead connected through suitable intermediate areas. The estimated "area of occupancy" of S. atra aurorae is 26 km2.
Habitat Areas inhabited by S. atra aurorae are in the range 1200–1800 m and include both moderately inclined slopes and narrow valleys facing south. The substrate is rocky, calcareous and karstic. Most sites are covered with forest stands with Beech, Silver Fir and Norway Spruce, with variable abundance of leaf litter, dead wood on the ground, and patches of grass and moss. Only a few records are from shrubby meadows. In the area of the Bosco del Dosso, S. atra aurorae inhabits only the inner parts of the forest, where old-growth stands of Silver Fir with Beech are apparently more suitable than thicker stands dominated by Norway Spruce. Among adults, habitat requirements are similar between males and females.
Life cycle The life cycle of S. atra aurorae has been investigated only in part, but is probably similar to that documented for S. atra atra. The embryonic and larval development are completed in the uteri of the mother and take at least two years. The juvenile is born after completing metamorphosis, even though it may retain small residuals of gills for a period. Usually two juveniles are born together by a pregnant female.
Behaviour Individuals overwinter underground, most probably at some depth in the soil, where they remain inactive for at least 6 months. Since late April to mid October, instead, they still spend most part of the time resting in the soil, however often in the most upper level, sometimes concealed under occasional shelters (e.g., stones emerging from the ground, dead wood or pieces of barks on the surface). During this period, they exit and move on the surface only when the surface is wet and the air is very humid, especially after intense rains following dry periods, independently from the daily cycle of light. At difference from other S. atra, S. atra aurorae does not exit regularly every day around dawn. Adult males are apparently more prone to epigean activity than females and juveniles. While juveniles disperse during the yearly season, adults are sedentary and remain within their home range also between years. Different shelters are used by a single individual within its home range, which is a few tens of square metres on average, without any obvious differences between males and females. Individual home ranges are partially overlapping, also between individuals of the same sex. The population density has been estimated up to hundreds of individuals per hectare.
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