Description
Tylototriton notialis is a stout bodied salamander with a total length of 109.1-141.8 mm (snout-vent length 56.5-73.4 mm). There are many small glandular warts spread over the entire body, giving the skin a rough appearance. Head is broader than the body, longer than it is wide, and sloping. The snout is short, truncate viewed from above, rounded when viewed from the side. T. notialis has enlarged parotoid glands which extend beyond the back of the head. A distinct ridge runs from the back of the head, down the spine to the tail. Two rows of pronounced glandular warts (about 14 in each row) run down either side of the dorsum. There are four fingers on each hand and five toes on each foot, none of which are webbed. The tail is flattened, with a narrow dorsal fin and a smooth ridge ventrally (Stuart et al. 2012).

T. notialis can be distinguished from other members of the T. asperrimus group by the knob-like nature of its rib nodules, and by its skin texture and coloration (in particular, the orange coloration present on the parotoids, which is absent in all other members of the group) (Stuart et al. 2012).

Coloration in life: The base coloration of T. notialis is dark brown, over both the dorsal and ventral surfaces. The glands which run down its back, the posterior portion of the parotoids, the tips of the toes, the edges of the ventral surfaces of the hands and feet, the cloaca, the top margin of the dorsal fin, and the ventral ridge of the tail are all bright orange. Some yellow spotting is present on the anterior surfaces of the limbs. The iris is dark brown (Stuart et al. 2012).

Coloration in preservation: The body fades to a lighter brown, and previously orange regions fade to yellow or a creamy yellow color (Stuart et al. 2012).

Variation: Some T. notialis may have black coloration instead of dark brown. It has been observed in the closely related T. vietnamensis that individuals found on land are darker in coloration than those found in the water (Stuart et al. 2012).

Larvae: T. notialis larvae have been found in two size classes. One larva measured 33.1 mm in length; nine others were between 17.8 and 20.9 mm. They were found at the bottom of a slow moving stream with sand and bedrock substrate (Stuart et al. 2012).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Lao People's Democratic Republic

View distribution map in BerkeleyMapper.

T. notialis is only known from the type locality, Nakai-Nam Theun National Protected Area in Khammouan Province, central Laos. It is expected to occur in Vietnam as well, however, based on its presence near the border.

T. notialis inhabits evergreen forests mixed with deciduous and pine. Individuals may be found in streams or on the forest floor. It is found at elevations of between 980 and 1,000 meters above sea level (Stuart et al. 2012).

Trends and Threats
Many Asian salamander species are threatened by overharvesting for the pet trade or for traditional Eastern medicine. It is hoped that the species' location (within a remote part of a protected area), as well as its muted coloration and similarity to other members of the T. asperrimus group will prevent exploitation of T. notialis for the pet trade (Stuart et al. 2012).

Relation to Humans
Related species have a history of collection for the international pet trade.

Possible reasons for amphibian decline

General habitat alteration and loss
Intentional mortality (over-harvesting, pet trade or collecting)

Comments
The species authorities for T. notialis are Ryan L. Stuart, Somphouthone Phimmachak, Niane Sivongxay, and William G. Robichaud.

The species name, notialis, is a Latin word for "southern", referring to the fact that T. notialis is the southernmost member of the T. asperrimus group.

T. notialis is a member of the T. asperrimus group, and appears to be most closely related to T. vietnamensis.

The type locality of T. notialis is located near the former Ho Chi Minh Trail, which was used during the Vietnam War by the North Vietnamese and their allies to move troops and supplies into South Vietnam. The paratype male was found 3 meters from an undetonated bomb dropped by American forces during the war (Stuart et al. 2012).

References

Stuart, B.L., Phimmachak, S., Sivongxay, N., Robichaud, W.G. (2010). ''A new species of the Tylototriton asperrimus group (Caudata: Salamandridae) from central Laos.'' Zootaxa, 2650, 19-32.

Species Account Citation: AmphibiaWeb 2013 Tylototriton notialis: Khammouan Crocodile Newt <https://amphibiaweb.org/species/7585> University of California, Berkeley, CA, USA. Accessed Nov 21, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 21 Nov 2024.

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