The first Pachytriton specimen was incorrectly described by David, 1875, as Cynops sinensis (Zhao, 1988). This was most likely based on morphological and geographical observations, such as the blackish body, bright colored belly, Asian origin, and aquatic behavior. Later, a similar species  was described by Sauvage as Triton brevipes, and in 1878, Boulenger coined the name Pachytriton, and applied it to Triton brevipes, making it Pachytriton brevipes (Zhao, 1988).  Another new species was discovered by Unterstein in 1930, which he named Molge labiatum, and which was considered a synonym of Pachytriton brevipes by Pope in 1931, and then a subspecies by C.C. Liu in 1973 (Zhao, 1988). The two subspecies of Pachytriton brevipes were later considered separate species based morphological differences, and the fact that there is no evidence of hybrids in the overlapping distributions. Today, there are two recognized species, Pachytriton labiatus (=labiatum), and Pachytriton brevipes.

There is still more work to be done with the genus Pahchytriton, as there are three unknown forms appearing in the pet trade; Pachytriton A, B, and C, and perhaps a fourth, Pachytriton D, for which there is currently limited information about. Pachytriton A and B are relatively similar to both P. labiatus and P. brevipes, and one hypothesis describes them as hybrid brevipes x labiatus individuals. If this is true, P. labiatus and P. brevipes may be placed back into the same species. Other theories place them as separate species altogether. The third unknown form, Type C, is notably different in physical appearance than the other unknown forms and species, and is likely an entirely new species. Some have even speculated as to the need for a new genus just for this type. Unfortunately, there is no distribution or origin information for these mystery creatures, as is the nature of the pet trade, and until genetic research says otherwise, they are simply treated as unknown forms.

Pachytriton labiatus (Unterstein, 1930) Spotless Paddle Tail Newt

Taxonomic Synonyms: Molge labiatum (Unterstein, 1930), Pachytriton brevipes (Hu, Zhao, Liu, 1973), Pachytriton labiatus (Zhao & Hu, 1984)
Vernacular Names: Paddle Tail Newt, Spotless Paddle Tail Newt, Spottless Stout Newt, Unterstein's Newt

The dorsum of Pachytriton labiatus is usually chocolate brown, or almost black, with or without broken, orange, dorsolateral stripes. Like all Pachytriton newts, except Type C, the skin is very smooth, lacking the rough texture characteristic of other newt species. The ventral surface is bright orange or reddish, mottled with black coloration. This pattern is similar to some newts of the genus Cynops. The tail is as long as, or slightly longer, than the body, with a prominent paddle-shaped tip. The tail is used for propulsion through flowing streams in the wild, and the shape distinguishes Pachytriton sp. from other newt species. The limbs are short, with stubby digits that are noticeably less defined than those of P. brevipes, and that almost appear webbed (Theismeier & Hornberg, 2003). The differentiation of toe form is most noticeable in the hind feet of both species. P. labiatus are also slimmer, and slightly shorter than P. brevipes, attaining lengths of 6-6.5 inches on average (Theismeier & Hornberg, 2003); however, some have reported larger individuals. Breeding males will develop one or more bluish-white spots or blotches along the distal end of the tail, and swollen cloaca. P. labiatus, and P. brevipes are known to develop lighter coloration with age, a characteristic more prominent in P. brevipes (Theismeier & Hornberg, 2003).

Breeding behavior is similar to Triturus and Cynops, in that males seek out females, and fan pheromone secretions toward them with the tail. P. labiatus males attempt to lead females off, while tail-fanning. An interested female will follow the steps of the male, nudging his cloaca with her snout periodically (Theismeier & Hornberg, 2003). The male will then deposit one or more spermatophores onto the substrate, in hopes that at least one adheres to the females cloaca as she passes over. Females will deposit eggs onto the roofs and sides of caves and crevices, and will aggressively guard them against any intruders. Interestingly, females have also been known to consume their own eggs. Because of their defensive behavior, fertilized females should be housed alone to avoid fighting and attacks against other newts. 

Females produce a rather small number of eggs in captivity, usually around 40-50 for the entire season (Theismeier & Hornberg, 2003). This is rather low compared to other newt species, such as Triturus and Cynops, which may produce hundreds of eggs in a single season. P. labiatus eggs are relatively large, around 4.4-4.5 mm, and hatch after about 2 months in temperatures of 55°F-66°F (13°F-16°F) (Theismeier & Hornberg, 2003). Warmer temperatures result in shorter incubation periods. Larvae hatch before complete development, for unknown reasons (Theismeier & Hornberg, 2003). Mature larvae are stream type, lacking balancers, and possessing short gills, and streamlined bodies. Larvae may begin metamorphosis after only a few months at moderate temperatures of around 60°F, and morphs are considerably small, around 35-42 mm (Theismeier & Hornberg, 2003). In captivity, young P. labiatus have been raised both aquatically and terrestrially. In the wild, P. labiatus juveniles are thought to live terrestrially for the first few years of life, before reaching sexual maturity and returning to the water. 

P. labiatus are thought to inhabit two disconnected areas in Eastern China (Zhao, 1988), where adults are presumed to remain completely aquatic. According to Zhao, et al., 1988, P. labiatus are found in two disconnected areas that include the Chinese Provinces of Guizhou, Guangxi, southern Hunan, and Zhejiang, and overlaps with P. brevipes in the Provinces of Guangxi and Hunan. Other references show maps that include Guangdong, and exclude Guangxi, while others include Jiangxi, Jiangsu, and Anhui. Although the southeastern populations overlap with P. brevipes, there is no confirmation of hybrids. It can be presumed that the exact range of P. labiatus is poorly known, especially in light of the unknown types appearing in the pet trade. It is also assumed that the the current distribution of P. labiatus has been reduced due to human encroachment, habitat loss, and pollution.

Pachytriton labiatus. Photo © Dr. Burkhard Thiesmeier, AG Urodela

Pachytriton labiatus. Photo © Dr. Burkhard Thiesmeier, AG Urodela

Pachytriton brevipes (Sauvage, 1876) Spotted Paddle Tail Newt

Taxonomic Synonyms: Cynops chinensis (David, 1875), Triton brevipes (Sauvage, 1876), Pachytriton brevipes (Boulenger, 1878), Pachytriton granulosus (Chang, 1933), Pingia granulosa (Chang, 1935)
Vernacular Names: Spotted Paddle Tail Newt, Spotted Stout Newt, Black-Spotted Stout Newt, Tsitou Newt

Pachytriton brevipes are similar in physical shape to P. labiatus, but differ in coloration and size. P. brevipes may be dark chocolate brown, with darker colored spots about the dorsum, head, and tail, or a light brown or tannish color, also covered in dark spots. The dark spotting is more difficult to see on browner individuals, and some may lack spotting altogether. The belly color and pattern is variable, and may consist of lighter color, with or without dark spotting, solid black coloration, or absent black coloration (Theismeier & Hornberg, 2003). Adults may reach 5.5-7.5 inches (14-19cm) (Theismeier & Hornberg, 2003). The labial folds are also more prominent than in P. labiatus. Like P. labiatus, P. brevipes possess the characteristic long paddle-shaped tail, short limbs, and stubby digits, however, the digits of P. brevipes are longer, and more distinguishable than P. labiatus, a characteristic especially noticeable in the hind feet (Theismeier & Hornberg, 2003). Breeding males will develop one or more bluish-white spots along the posterior end of the tail, and swollen cloaca. P. labiatus, and P. brevipes are known to develop lighter coloration with age, a characteristic that shows the dark spotting more clearly in P. brevipes (Theismeier & Hornberg, 2003).

The breeding requirements and behaviors of P. brevipes are still unknown.

P. brevipes are found in southeastern China (Zhao, 1988). According to Zhao, et al., 1988, P. brevipes are found in the Chinese Provinces of Guangxi, Guizhou, Jiangxi, Fujian, Zhejiang, and Hunan, and overlaps with P. labiatus in the Provinces of Guangxi and Hunan. Other references show maps that include Guangdong, and exclude Guizhou, while others show an overlap of P. brevipes and P. labiatus in the Provinces of Guangxi, Guangdong, and Hunan. The habitat is the same as P. labiatus, that is, cool, clean streams with high oxygen content. It is assumed that the the current distribution of P. brevipes has been reduced due to human encroachment, habitat loss, and pollution, and like P. labiatus, the exact range is poorly known. Although the southeastern populations overlap with P. brevipes, there is no confirmation of hybrids.

Pachytriton brevipes. Photo © Takeshi Ebinuma, endless@interone.jp	Pachytriton (brevipes). Photo © Paolo Mazzei, Amphibians and Reptiles of Europe
Pachytriton labiatus. Photo © Dr. Burkhard Thiesmeier, AG Urodela

For more photos, go to the Pachytriton brevipes gallery

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Unknown forms: Pachytriton ABC(D)

Three distinguishable, unknown newts have recently appeared in the the pet trade. Based on behavior and physical appearance, they are thought to be species or subspecies of Pachytriton, but are simply considered unknown forms for now. Each type does not completely fit the description of either P. labiatus, or P. brevipes, but has yet to be accurately described or classed due to the lack of origin and definitive life history information. 

Pachytriton A is similar in appearance to P. brevipes, but males develop bluish-white coloration on the entire tail, up to the cloaca. This unknown form also lacks conspicuous spotting, a distinguishing characteristic of P. brevipes (Theismeier, 2003). The shape of the hind toes is more similar to P. labiatus, but the toes are slightly more defined. Juvenile Pachytriton A have bright bellies, like P. labiatus adults, reddish dorsolateral stripes, and develop dark spotting with age (Theismeier, 2003). 

Despite the lack of origin and natural history, Pachytriton A has been successfully bred in captivity. Breeding behavior is very similar to that described in the Pachytriton labiatus section, above. For a breeding account of Pachytriton A, see Deutsche Gesellschaft für Herpetologie und Terrarienkunde, Salamandra Abstracts Volume 33, Number 2/97.

Pachytriton A. Photo © Dr. Burkhard Thiesmeier, AG Urodela

Pachytriton A. Photo © Dr. Burkhard Thiesmeier, AG Urodela

Pachytriton B are thought to be more similar to Pachytriton labiatus in physical appearance, but are larger, with lighter brown coloration, and more faded belly color. Pachytriton B may reach up to 7.10 inches (18cm), and are also more rectangular in shape when compared to P. labiatus (Theismeier, 2003). However, the hind toes are similar to P. brevipes in that they are longer, and more distinguishable than in P. labiatus (Theismeier, 2003).

Pachytriton B. Photo © Takeshi Ebinuma, endless@interone.jp

Pachytriton B (male). Photo © Dr. Burkhard Thiesmeier, AG Urodela

Pachytriton B (female). Photo © Dr. Burkhard Thiesmeier, AG Urodela

Pachytriton C are most likely the easiest to distinguish from the other unknown forms. They are olive green or brown with a greenish tint, some with dark markings along the back, tail, and head. The skin is almost leathery in appearance, and considerably rough compared to the smooth skin characteristic of Pachytriton spp., and the typical paddle-shaped tail is present. Some individuals may also possess a pale peach or yellow colored dorsal stripe that extends along the upper side of the tail. Pachytriton C will hibernate during the winter, at temperatures around 40°F (Wallays). Juveniles and adults can secrete a sticky, odorous mucus if disturbed, and adults may  "play dead" if disturbed during winter temperatures (Wallays). 

Pachytriton C has also been successfully bred in captivity. Courtship includes tail-fanning, which also may be displayed when the newt feels threatened. Males and females are increasingly aggressive during the mating season, and will attack approaching members of the same sex (Wallays). Eggs are attached to the sides of rock walls and crevices, and are guarded by the female. For more information and a breeding account, see the Moscow Webpage of Henk Wallays.

 

Pachytriton C. Photos © Thomas Mutz, AG Urodela

Pachytriton C. Photos © Thomas Mutz, AG Urodela

A possible new form has recently appeared, Pacytriton D. More information about this type will be added when available. Photos by Henk Wallays are available at http://www.livingunderworld.org/photos/showgallery.php?cat=500&ppuser=8. 

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Overview of P. labiatus and P. brevipes Housing Requirements
In the wild, P. labiatus and P. brevipes are thought to inhabit cold, oxygenated waters. In captivity, healthy individuals will remain fully aquatic in the right temperature range. A small land area may be required if the newts enter hibernation, or if one or more are bullied out of the water by more aggressive individuals. To avoid continuous aggression, some keepers find it necessary to house these newts separately outside of the breeding season, only introducing single male-female pairs during the breeding season. Pachytriton are aggressive, territorial newts, but can usually be housed in multi-member tanks if ample territory and hiding places are provided. Very large tanks may not be sufficient for excessively aggressive individuals, however. If they are seen fighting, or fighting wounds are found on any members, the culprits should be separated, as this species have been known to fight to the death. Two-three individuals can usually be housed in a large aquarium of 40 x 15 inches with plenty of hiding places, but again, this may not be large enough for some individuals. Exceedingly aggressive individuals may persistently seek out and attack any other members of the tank, regardless of the size of the tank. If a male-female pair enters breeding mode, it is best to separate them from others, as both males and females become increasingly aggressive during this time. Females will guard eggs in nest sites, and are thought to claim these spots early in the season (Theismeier & Hornberg, 2003). Like many other species, Pachytriton prefer cooler temperatures, and may develop health problems if exposed to high temperatures for long periods of time.

In general, Pachytriton are housed in stream-type environments with moderately deep, flowing water. A land area should be included if more than one newt is housed in the same tank, as a means of escape for a bullied newt. Again, newts that are excessively or continuously fighting should be separated to avoid stress and wounds. A few mossy rocks protruding from the waters surface are suitable for short term refuge for Pachytriton species. Generally, established and cohabitating individuals housed in spacious tanks will not use a land area at all. A filter or air pump can be used to simulate a moving stream in captivity, but should not create an overly-powerful current. Most filter outputs can be positioned to create flowing water throughout the tank. Oxygen rich water is essential for Pachytriton species, as low oxygen content waters are thought to produce sluggish behavior. It is recommended to create a few spots in the tank that are shielded from the water flow so that the inhabitants can choose the level of aeration they prefer. Rocks, driftwood, or thick vegetation in some areas work well to slow or block the current. The water level can be 6-20 inches deep, with some shallower areas in places. Because they require moderately flowing waters, thick vegetation is not recommended throughout the entire tank, however, a few rooted and/or floating plants can be added. As recommended by at least a few avid keepers, Pachytriton species are most active between 50°F and 65°F, and temperatures should not rise above 72°F for long periods of time.

It is recommended to keep a freshwater test kit on hand, and regularly check the pH, ammonia, nitrite, and nitrate levels, as is suggested with any aquatic species. The water area should support a filter with a carbon and sponge insert, or a canister type biological filter for larger tanks. The filter will aid in keeping the water clean of chemicals and pollutants, as well as provide adequate aeration. Gravel is the standard form of submersed substrate, however, some have used sand with no ill effects. Small fish, such as guppies or white cloud minnows, are sometimes added with this species, but keep in mind that fish can introduce harmful disease into the tank. Also, Pachytriton are capable of chasing and consuming small fish rather efficiently. See article 0020 - Captive Habitats: Ideas, Instructions, and Examples and the Captive & Wild Habitats section of the Photo Gallery. 

As with all amphibians, tap water should be treated with a water conditioner or primer prior to the introduction of amphibians. Never use plain tap water, de-ionized, distilled, or reverse osmosis water alone with amphibians. Also, the tank should be cycled (nitrogen cycle) prior to the introduction of amphibians to avoid health problems or death. See article 0006 - Water Quality and Amphibians and article 0009 - Introduction to the Nitrogen Cycle for more information about water quality and the importance of the nitrogen cycle.

Common Food Items
Pachytriton are aggressive hunters and feeders. Most individuals will eagerly accept frozen blood worms, chopped earthworms, maggots, waxworms, live tubifex or black worms, and just about any other type of bite-sized invertebrate offered. Pachytriton can become accustomed to feedings from forceps, and will also eagerly hunt down food items. 

Table 1.1 - Commonly available food items acceptable for captive Pachytriton species
Aquatic Larvae:	Terrestrial Adolescent:	Semi-Aquatic Adult:
» Black Worms » Blood Worms (finely chopped) » Brine Shrimp (newly hatched) » Copepods » Daphnia » Earthworms (finely chopped) » Fish Flakes (finely crushed) » Grindal Worms » Microworms » Tubifex Worms (finely chopped) » Paramecium » Scuds (Amphipods) » White worms	» Black Worms » Blood Worms » Crickets (gut-loaded pinheads - 2 week) » Earthworms/night crawlers (chopped) » Flour Beetles & Larvae » Fly Larvae (small) » Fruit Flies & Larvae » Grindal Worms » Grubs » Rice Beetles & Larvae » Springtails » Tubifex Worms » White Worms	» Black Worms » Blood Worms » Earthworms (chopped) » Fly Larvae (maggots) » Grubs » Tubifex Worms » Waxworms (small) » Small Crickets

Amphibians should be given a variety of different live foods to ensure proper nourishment and health. Chopped earthworm, black worms, blood worms, and maggots will work as semi-staple foods for semi-aquatic adults. Crickets are not recommended as a staple diet, as they can lead to nutritional disorders. For more information, see article 0002 - Amphibian Foods and Feeding Tips, and article 0001 - Common Amphibian Ailments.

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Journal References

Thiesmeier, Dr. Burkhard, and C. Hornberg (1992). First evidence of parental care in the Chinese salamander, Pachytriton brevipes. AActa Biol Benrodis, Dusseldorf 4: 163-164.

Sparreboom, Max, and B. Theismeier (1999). Courtship behaviour of Pachytriton labiatus (Caudata: Salamandridae). Amphibiaa-Reptilia 20: 344-349.

Literature References

Obst, Fritz Jugen, Udo Jacob, and K. Richter. Completely Illustrated Atlas of Reptiles and Amphibians for the Terrarium.
   Neptune City, NY: T.F.H. Publications, Inc., 1989.

Theismeier, Dr. Burkhard, and Claudia Hornberg. 2003. The Riddle of the Chinese Newt, Pachytriton.
   Reptilia, The European Herp Magazine, 2003.

Zhao, E. China Red Data Book of Endangered Animals: Amphibia and Reptilia.
   Beijing, China: Science Press; Endangered Species Scientific Commission, P.R.C., 1998.

Zhao, E., et al. Studies on Chinese Salamanders.
   Society for the Study of Amphibians and Reptiles, 1988.

Internet References

AmphibiaWeb. (2003). http://amphibiaweb.org/. (Accessed: 2001-2003).

Ancillotto, Leonardo. I leoni tra i tritoni: Pachytriton & Co. Amici Insoliti. http://www.amiciinsoliti.it/anfibi/pachytriton.html (Accessed: 2002).

Thiesmeier, Dr. Burkhard. (1997). Courtship, reproduction and larval development of Pachytriton sp. (Pachytriton A) with comments on the taxonomy of the genus. Salmandra Abstracts, Deutsche Gesellschaft für Herpetologie und Terrarienkunde. http://www.dght.de/salamandra/sala2_97E.htm (Accessed: 2002).

Wallays, Henk. New species of the genus Pachytriton. Moscow Webpage of Henk Wallays. http://www.callisto.ru/amphibia/henk/hwpage.htm (Accessed: 2001).