The blue-spotted salamander hybridizes with the spotted salamander, the Jefferson salamander, and the tiger salamander. The hybrid between blue-spotted salamander and Jefferson salamander is called A. platineum. It is a unisexual clonal triploid. This hybrid reproduces gynogenetically. Gynogenetic reproduction is where sperm from a host species is needed to activate the egg development but makes no genetic contribution (Spolsky 1992). The hybrid species are dependent upon one of the parental species.
Due to the loss of wetlands and the destruction of forests, the salamanders are threatened. However, there is no evidence of decline in the blue-spotted salamander as of yet (CCIW 1999). Blue-spotted salamanders are more tolerant to human disturbances than other salamanders. They still persist in fragmented forests (Harding 1997).
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
IUCN Red List of Threatened Species: least concern
Development - Life Cycle: metamorphosis
Blue-spotted salamanders consume many mosquitoes each year (Harding 1997).
The Blue-spotted salamander is a carnivore. The adult eats worms, snails, slugs, insects, centipedes, spiders and other invertebrates. The larvae eat small aquatic invertebrates such as water fleas (cladocerans), copepods, insects and insect larvae, especially mosquito larvae (Harding 1997). The diet suggests that the feeding ground is beneath leaf litter in forests (Collicut 1999). In captivity, blue-spotted salamanders survive on 1 worm a week (Collicut 1999).
Blue-spotted salamanders are found from eastern central North America and stretch in a broad band across to the Atlantic Provinces and northern New England. They are found around the Great Lakes and west as far as central Manitoba. They reach as far north as James Bay, Ontario (Collicutt 1999).
Biogeographic Regions: nearctic (Native )
The blue-spotted salamander lives in deciduous and coniferous forests. They are most abundant in moist woodlands with sandy soil. They differ from other salamanders in that they are found above ground throughout the warmer months (Harding 1997). During the day they stay undercover out of the direct sunlight. They spend the summer and fall in damp forests, searching for food at night (Nova Scotia 1999).
Habitat Regions: temperate ; terrestrial
Terrestrial Biomes: forest
Aquatic Biomes: lakes and ponds
Length: 10-14cm.
Blue-spotted salamanders have a long tail that is approximately 40% of its body length (Collicutt 1999). The salamander's tail is broadly oval at the base and compressed towards the tip. It is fleshier than A. jeffersonianum (Minton 1972). They also have a slimmer body than the tiger salamander A. tigrinum (Collicut 1999). Their feet have relatively long toes (Conant and Collins 1998). They are given their name for the bluish-white spots and flecks on the tides of the trunk and tail and also sometimes on the back. Their skin is bluish-black (Conant and Collins 1998). The spots are also on their limbs and belly (Harding 1997). The belly may be either black or a lighter shade than the dorsum, but the vent is usually black (Harding 1997). There is some slight size difference between the males and the females. The males tend to be slightly smaller than the females, the males also have a longer more flattened tail (Harding 1997). The larvae of blue-spotted salamanders vary in appearance. When the larvae are small and relatively young they have broad tail fins and external gills for living in the water (Collicutt 1999). But once they have developed all four legs they appear to be dark brown, olive or gray on the upper surface with dark mottling on the fail fins. They also may have dull yellow blotches on the dorsum or yellowish stripes down each side of the back. The belly is lighter and unmarked (Harding 1997).
Other Physical Features: ectothermic ; heterothermic ; bilateral symmetry
The life span of a blue-spotted salamander is unknown (Collicutt 1999). Both male and females reach maturity at about 2 years of age (Harding 1997). The salamander breeds in woodland ponds and ditches (Conant and Collins 1998). They breed in April in small ponds. The female lays as many as 500 eggs individually at bases of sticks, plants or rocks. The eggs take about 1 month to hatch, and when they hatch they have well-developed eyes, mouth, external gills, and broad tail fins. At two weeks old, the front legs form and at 3 weeks the hind limbs are formed. As they get older they look like tiny adult salamanders except they have broad tail fins and external gills. Between 3-5cm in length they transform into the adult form and leave the pond. When they transform they loose their external gills and tail fins and develop the adult coloration (Collicut 1999). They transform in late summer (CCIW 1999).
Key Reproductive Features: seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (Internal ); oviparous
The silvery salamander (Ambystoma platineum) is a hybrid species of mole salamander from the United States of America and Canada. It is usually between 5.5 – 7.75 in (12 – 19.9 cm) long and is slender with many small silvery-blue spots on its back and sides. It is brownish grey and the area around its vent is grey. This unisexual Ambystoma hybrid species,[1] has been grouped with other unisexual ambystomatids that takes genetic material from Jefferson salamander (A. jeffersonianum), streamside salamander (A. barbouri), small-mouthed salamander (A. texanum), tiger salamander (A. tigrinum) and the blue-spotted salamander (A. laterale).
"Species name designations for unisexual Ambystoma are no longer in use".[2] Instead, unisexual Ambystoma are now considered distinct biotypes rather than species.[3]
Lacking its own males, the LJJ biotype breeds with male blue-spotted or Jefferson salamanders from March to April. The males' spermatophores only stimulate egg development; their genetic material does not contribute to the offspring's DNA. This mode of reproduction (a form of natural cloning) is called gynogenesis. The females lay cylindrical egg masses and attach them to underwater twigs. This salamander is not often observed and its diet and lifestyle are unknown.
These salamanders live almost anywhere between south-central Michigan to adjacent Indiana and Ohio to western Massachusetts south to northern New Jersey. They are commonly found in or near shallow rivers and ponds in deciduous forest. There is an extremely limited population of the salamanders in Vermilion County, Illinois with only one remaining natural population known. They are considered endangered within the state. Theory states that the population may have dropped due to the vernal pool in which they live not retaining water for a long enough period for their tadpoles to reach metamorphosis.[4]
The LJJ biotype's predators include birds, fish, raccoons, and dogs.
Their diet is mainly slugs, ants, spiders, soft insects, and worms.
The silvery salamander (Ambystoma platineum) is a hybrid species of mole salamander from the United States of America and Canada. It is usually between 5.5 – 7.75 in (12 – 19.9 cm) long and is slender with many small silvery-blue spots on its back and sides. It is brownish grey and the area around its vent is grey. This unisexual Ambystoma hybrid species, has been grouped with other unisexual ambystomatids that takes genetic material from Jefferson salamander (A. jeffersonianum), streamside salamander (A. barbouri), small-mouthed salamander (A. texanum), tiger salamander (A. tigrinum) and the blue-spotted salamander (A. laterale).
"Species name designations for unisexual Ambystoma are no longer in use". Instead, unisexual Ambystoma are now considered distinct biotypes rather than species.
