Mud salamander

Pseudotriton montanus
Conservation status
Least Concern  (IUCN 3.1)[1]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Amphibia
Order:	Urodela
Family:	Plethodontidae
Subfamily:	Hemidactyliinae
Genus:	Pseudotriton
Species:	P. montanus
Binomial name
Pseudotriton montanus Baird, 1850

The mud salamander or mountain triton (Pseudotriton montanus) is a salamander in the family Plethodontidae.^[2] It is a red salamander with black spots that inhabits swamps, bogs, and streams. It is often confused with the red salamander, but the mud salamander is distinguished by its dark eyes and short snout. It is indigenous to the eastern United States, but is currently an endangered species. Some states have programs to locate mud salamanders to try to keep the species alive.

Taxonomy

The taxonomy of Pseudotriton montanus and its closest relatives is unsettled. Several subspecies have been described, and some of these might warrant full species rank. In particular, Pseudotriton diastictus maybe treated as a species or a subspecies (Pseudotriton montanus diastictus).^[2] The rest of this article is following the latter position.

Description

The mud salamander is known for its reddish-brown color, brown eyes, stocky girth, and short tail. It also has between 30 and 40 distinct round black spots on its back by the time it reaches adulthood.^[3] Younger mud salamanders are typically colored bright red, orangish-brown, or crimson,^[4] with unmarked stomachs and separated spots, while older mud salamanders’ colors darken with age and take on more of a brown coloring. They also acquire more spots, larger spots, and spotted stomachs.^[5] They can reach lengths of 3-8 in (7.6 to 20 cm) in adulthood, and are typically stocky.^[6] Red salamanders and mud salamanders are very difficult to distinguish from each other. The main differences are in their eyes and snouts. While the mud salamander has dark brown eyes and a short snout, the red salamander has bright yellow eyes and a long snout.^[7]

Reproduction

Mud salamanders breed during the warmer months of the year. Egg deposition commonly occurs during autumn and winter. The females reproduce at most once per year (usually once per two years), while males may breed several times a year. “When a mate is found, the male performs a tail undulation display. The female then straddles his tail, allowing glands on the male's tail to lubricate her. The male is then able to deposit his sperm into the female”.^[8] Females reach reproductive maturity around four to five years old, while males reach reproductive maturity around two to two and a half years old. “A female may stay with her eggs to aid the incubation process. Incubation typically lasts three or more months, with embryos hatching in the winter. Clutches range in size between 65 and 200.”^[9]

Habitat

The mud salamander inhabits swamps in low elevations, bogs, seeps, springs, and streams that not only provide a muddy bottom, but also clean and clear water. The mud salamander, a burrowing species, seeks shelter in burrows beneath leaf litter, logs, stones, or bark. The mud salamander may also build tunnels in creek banks, as well. These amphibians spend most of their lives in close proximity to water, but also burrow into the soil of the surrounding area. Larvae are usually underground in muddy springs; they are often found in leaf litter, debris, and muck of muddy springs, seeps, and streams. After they lose their gills and become adults, they make burrows in muddy areas. They often use burrows of crayfish and will sit with their heads sticking out of these burrows waiting for prey to pass by. They come out of these burrows at night and forage in the surrounding area. Generally, mud salamanders do not wander as far from their main habitat as their close relatives, the red salamanders. Mud salamanders seem to favor small, muddy seeps and springs that dry up in the summer. Both larval and adult mud salamanders go deep underground during the hottest months of the summer, especially in the small springs and seeps that dry up. The gilled larvae go deep in the mud where the water is underground and the adults remain deep in burrows. During the hottest times of the year, they are usually only found at night or during rains foraging for a short time before they return to their burrows in the mud. Dusky salamanders are often found in the same habitat as mud salamanders and are much easier to find than the mud salamanders. When this is the case, the more abundant dusky salamanders often serve as a food source for the mud salamanders. There are many scenarios where small muddy springs where mud salamanders live feed into larger streams that have more common species such as dusky and two-lined salamanders. In this case, the muds venture into the main stream and can often be found in it because they are looking for more food outside of their smaller more primary habitat. Some reasons for this is less competition outside of a smaller habitat full of mud salamanders, another reason is the abundant two lined and dusky salamanders that are food for the larger muds. They can often be found in creeks that do not seem like ideal habitat for them because they have ventured out of their primary habitat for food. Chances are an ideal muddy habitat is within walking distance from where the mud salamander was found in the stream.^[10]

Diet

A mud salamander's diet varies with age. In the larval stage, the small creatures tend to feed on equal-sized or smaller, aquatic invertebrates.^[11] The salamander larvae are also said to consume other salamander larvae.^[12] As an adult, though, the salamander's diet increases in variety, but it still eats smaller prey. Though not much is known about an adult salamander’s eating habits,^[13] it is known that they are likely to feed on earthworms, beetles, spiders, and even smaller kinds of salamanders.^[14] Mud salamanders also can eat insects as small as mites.^[13] What the mud salamander tends to eat however, mainly lies in the habitat in which it lives.

Conservation status

Because of the mud salamander's extreme rarity in Virginia, it was put on the threatened species list in 1979. The Virginia Herpetological Society regards this species to be secure globally, but in danger in Virginia because of its extreme rarity there.^[15] Many surveys and searches were run in the 1980s to locate the populations of the mud salamander in western Virginia. Although efforts were great, few sightings of this species were made. Because little information about the species is known, it is difficult to find possible threats, but threats to other types of salamanders probably affect mud salamanders. Tristan Clark has found multiple populations in East Tennessee in Sullivan and Hawkins county. Because this species is so hard to find, it is important to be treated as an endangered species in any state because enough specimens cannot be found to have an idea of their true abundance. (Clark, 2014) UPDATE several located in Macon County North Carolina (12/15/2015) ^[16] Update: 4/24/2016 found in National Forest in Lumpkin County, near Dahlonega, GA.

References