Species account

Neurergus crocatus Cope, 1862

Lake Urmia Newt

Description
Large-bodied newt. Head flattened, longer than wide. Snout rounded. Paratoids not prominent; gular fold present. Trunk almost round, rather slender, without dorsal ridge, but with slight vertebral depression. Tail longer than snout-vent length, rounded at the base, compressed laterally toward the tip. Tail-tip blunt. Moderately developed tail fins on dorsal and ventral sides; dorsal tail fin a little higher, especially in the breeding season. Limbs well developed and broadly overlapping when laid against the body. Hind limbs thicker than front legs in both sexes. Toes and fingers thick and flat (Freytag, 1957).Skin of dorsal side granulated and wrinkled, with scattered small warts. In terrestrial phase, the skin is dry and rough, not shiny as in Salamandra. Ventral side smooth. Lungs reduced.

Dorsal colour dark brown to black with yellow, rounded, irregular blotches. Similar spots on the sides of the tail. Ventral surface orange-red in the male, yellowish in the female.

Cloaca half rounded in the male, swollen in the breeding season, with a longitudinal slit. Cloaca conical in the female with a rounded opening and protruding (Schmidtler & Schmidtler, 1975). The male does not develop a silver-blue colouration of spots along the tail, as in N. strauchii.

Total length between 16 and 18 cm (Schmidtler & Schmidtler, 1975).

Diagnosis
Yellow dorsal blotches larger than in N. strauchii; ventral side orange-red in males, yellowish in females. Female cloaca slightly protruding in breeding season.

Eggs and larvae
Oviposition in March-April. Eggs are laid in clutches of 150-200 on the lower surface of flat stones in mountain streams. Jelly capsule approx. 6-9 mm in diameter, the embryo diameter is 1.5-2.0 mm (Steinfartz, 1995; Timofeev, 1997). Eggs are joined by a jelly string. Incidentally more eggs in one capsule are found. At water temperatures averaging 16º C, larvae hatch after 25-27 days at a length of 11 mm (Steinfartz, 1995) or 13-14 mm (Schultschik, 2006). Metamorphosis takes place after four (Schultschik, 2006) or five to six months at a length of 60-70 mm (Timofeev, 1997). Growth is slow and sexual maturity is reached after four to five years (Schultschik, 2006; Thorn & Raffaelli, 2001). Larvae have a slender body-form. The dorsal tail-fin reaches well onto the middle of the body. Tail-tip rounded. Short gills. Younger larvae are bright grey with irregular black spots, older larvae have irregular, large bright blotches. Ventral colour uniformly light. Tail of older larvae more or less clearly pigmented (Schmidtler & Schmidtler, 1975). For comparative larval morphology of N. crocatus and N. strauchii, see Schmidtler & Schmidtler (1975) and Steinfartz (1995).

Distribution

The Lake Urmia Newt is distributed in the mountains west of Lake Urmia in northwestern Iran, in southeast Anatolia, Turkey, and in the Kurdish region of northern Iraq. (IUCN, Conservation International, and NatureServe, 2006).

Habitat
Springs and mountain brooks in shaded valleys, between 500 and 1,500 m altitude (Schmidtler & Schmidtler, 1975). Baran and Atatür (1998) cite a vertical distribution of 1,500 to 2,000 m.

Behaviour
Hibernation probably from December to end February. Breeding takes place in mountain streams, probably from March to May (Steinfartz & Schultschik, 1997). Newts leave the water for surrounding areas after breeding, but the terrestrial habitat remains unknown. Probably the adults stay under rocks during winter (IUCN, Conservation International, and NatureServe, 2006).

Reproductive behaviour was studied in captive specimens originating from Aqrah in northern Iraq. The male takes up a position in front of the female, from where he starts a tail-fanning display, fanning his tail in the direction of her snout. By moving forward towards the male the female signals that she is responsive. The male makes a few steps backward, then turns away from the female and creeps ahead of her, his tail making undulating movements. The female follows him, touching his tail. The male deposits a spermatophore, moves forward and makes a 90º turn, bringing him back into a position perpendicular to the female’s body. He stops (brakes) the female in her progress at a point when her cloaca is situated above the place where the spermatophore was deposited. This behaviour was found to be similar in N. strauchii, N. crocatus and N. kaiseri. For N. microspilotus observations are uncertain. In its general pattern, this courtship behaviour is similar to that of small European pond breeding newts and of Asian Cynops, Pachytriton and Paramesotriton (Sparreboom et al., 2000).

Threats and conservation
The species is considered to be relatively susceptible to habitat change, habitat loss, pollution, drought and collection. The species is protected by national legislation in Iran (IUCN, Conservation International, and NatureServe, 2006).

Observations in captivity
Neurergus crocatus has been bred in captivity on several occasions, but keeping the animals alive for longer periods, and rearing the juveniles has proven to be problematic (Steinfartz, 1995; Timofeev, 1997; Wallays, 2002; Schultschik, 2006). The newts should be kept in tanks with cool and running water, providing enough hiding places with flat stones. In captivity the animals can be kept aquatic almost all year round, but for breeding success a terrestrial phase is recommended. The data on eggs and larvae, and the observations on courtship and oviposition reported above have been made on captive animals.

Comments

Knowledge of this species is still mainly based on the reports of Schmidtler & Schmidtler (1970, 1975) and Schmidtler (1994). For Iranian references see Baloutch & Kami (1995). For earlier literature see Freytag (1957).

Neurergus crocatus 2
Neurergus crocatus
© 2008 Sergé Bogaerts

References
Baloutch, M. & Kami, H.G., (1995). Amphibians of Iran. Tehran University Publications 2250, Tehran.

Baran, I. & Atatür, M.K., (1998). Turkish Herpetofauna (Amphibians and Reptiles). Ankara.

Freytag, G.E., (1957)."Bemerkungen über den salamanderartigen Bergmolch Neurergus crocatus." Abh. Ber. Naturk. Vorgesch., 10: 39-58.

IUCN, Conservation International, and NatureServe, (2006). "Global Amphibian Assessment." www.globalamphibians.org. Accessed May 2006.

Leviton, A.E., Anderson, S.C., Adler, K. & Minton, S.A., (1992). Handbook to Middle East Amphibians and Reptiles. Society for the Study of Amphibians and Reptiles.

Schmidtler, J.F., (1994)."Eine Übersicht neuerer Untersuchungen und Beobachtungen an der vorderasiatischen Molchgattung Neurergus." Abh. Ber. Naturkde, Magdeburg, 17: 193-198.

Schmidtler, J.J. & Schmidtler, J.F., (1970)."Morphologie, Biologie und Verwandschaftsbeziehungen von Neurergus strauchii aus der Türkei." Senckenbergiana biol., 51: 41-53.

Schmidtler, J.J. & Schmidtler, J.F., (1975)."Untersuchungen an westpersischen Bergbachmolchen der Gattung Neurergus (Caudata, Salamandridae)." Salamandra, 11: 84-98.

Schultschik, G., (2006)."Neurergus crocatus (Cope, 1862)." http://www.salamanderland.at. Accessed November 2006.

Sparreboom, M., Steinfartz, S. & Schultschik, G., (2000)."Courtship Behaviour of Neurergus." Amphibia-Reptilia, 21: 1-11.

Steinfartz, S., (1995)."Zur Fortpflanzungsbiologie von Neurergus crocatus und Neurergus strauchii barani." Salamandra, 31:15-32.

Steinfartz, S. & Schultschik, G., (1997)."Die Gattung Neurergus. Faszinierende Bergbachsalamander aus dem Nahen Osten." Reptilia, 43: 43-48.

Thorn, R. & Raffaelli, J., (2001). Les salamandres de l’Ancien Monde. Boubée, Paris.

Timofeev, B.I., (1997)."Notes on the Reproduction of Neurergus crocatus in Captivity." Advances in Amphibian Research in the Former Soviet Union, 2: 173-176.

Wallays, H., (2002)."Neurergus crocatus – Urmia-beeksalamander, observaties en kweekverslag." Pp. 36-37 in: Bouwman, A. & Bogaerts, S. (red.) Salamanders, jubileumbundel ter ere van het 20 jarige bestaan van de Salamandervereniging. Nijmegen.

Monday, May 11, 2009 author: M. (Max) Sparreboom