Azemiopinae

Name

Azemiopinae Liem, Marx & Rabb, 1971

Vernacular Names
Deutsch: Fea-Viper
English: Fea Viper

Azemiopinae is a monotypic subfamily created for the monotypic genus, Azemiops, that contains the venomous viper species A. feae, described here. No subspecies are recognized.[3] The first specimens were described by European explorer M.L. Fea, with the genus later being described by Boulenger in 1888.[2] Considered to be one of the most primitive vipers,[4] it is found in the mountains of South East Asia[5] in China, southeastern Tibet and Vietnam.[2]

Description

This species does not grow to more than 1 m in length. According to Liem et al. (1971), the maximum length is 77 cm, while Orlov (1997) described a male and a female measuring 72 cm and 78 cm respectively.[2]

Considered to be the most primitive of all viperids for a number of reasons. It has a reasonably sturdy body and a short tail, but the dorsal scales are smooth rather than keeled like those of most vipers. The head, which is slightly flattened and more elliptical in shape than triangular, is not covered with numerous small scales like most other vipers, but with large shields like the colubrids and the elapids. Also, the skull is built differently. It does, however, have a pair of hollow, rotating fangs, although these are short. The fangs have a ridge at the tip lateral to the discharge oriface, as well as a blade-like structure on the ventral surface otherwise seen only in some opistoglyphous and atractaspid snakes. The venom glands are relatively small. Finally, unlike most vipers, the Fea's viper is oviparous and hibernates during the winter months.[2]

The color pattern of the Fea's viper is striking: its basic body color is a shiny, deep blue-gray to black and marked by a number of widely spaced thin (1-2 scales) white-orange bands. The head is orange to slightly yellow with a distinct cross-pattern outlined in gray. The eyes are yellowish with vertical pupils.[2]

Geographic range

Ranges from northern Vietnam through southern China (Fujien, Guangxi, Jiangxi, Kweichow, Sichuan, Yunnan, Zhejiang), south-east, Myanmar and south-east Tibet. The type locality is listed as "Kakhien Hills (Kachin Hills), Myanmar."[1]

Habitat

Found in mountainous regions at altitudes up to 1000 m. Cooler climates are preferred, with an average temperature of 20-25 °C. Sometimes it is found on roadsides, in straw and grass, in rice fields, and even in and around homes. In Vietnam, its preferred habitat is described as forests of bamboo and tree ferns, with clearings, where the forest floor is covered with rotting vegetation, where there are plenty of rock outcroppings and there are many open and subterranean streams. The species is crepuscular, prefers temperatures of 18-25 °C, and very moist environments for shelter.[2]

Behavior

This species has a characteristic threat display. When disturbed, it flattens its body to make itself look wider, and its jaws flare outwards posteriorly, giving the normally ovoid head a triangular shape. Sometimes, it will vibrate its tail. Ultimately, it will strike, during which it may or may not use its fangs. As opposed to Orlov (1997), who states that this species is nocturnal, Zhao et al. (1981) report that it is crepuscular, being active from early March into late November.[2]

Feeding

They apparently feed on small mammals. A captured, immature specimen was found to have eaten a common gray shrew (Crocidura attenuata). In captivity, these snakes are reported to be reluctant feeders, but when they did they took newborn mice, and then only at night. On several occasions when feeding was observed, the prey was not released after being struck.[2]

Venom

Research conducted by Dr. Bryan Grieg Fry indicates that the venom profile of the Fea's viper is remarkably similar to that of the Wagler's viper (Tropidolaemus wagleri).[6] Another study found that enzyme activities in Azemiops feae venom gland extract are similar to those of viperine venoms, except that Azemiops venom has no blood clotting, haemorrhagic or myolytic activities. [7]

References

1. ^ a b c d McDiarmid RW, Campbell JA, Touré T. 1999. Snake Species of the World: A Taxonomic and Geographic Reference, vol. 1. Herpetologists' League. 511 pp. ISBN 1-893777-00-6 (series). ISBN 1-893777-01-4 (volume).
2. ^ a b c d e f g h i Mallow D, Ludwig D, Nilson G. 2003. True Vipers: Natural History and Toxinology of Old World Vipers. Krieger Publishing Company. 359 pp. ISBN 0-89464-877-2.
3. ^ "Azemiops feae". Integrated Taxonomic Information System. http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=634834. Retrieved 23 August 2006.
4. ^ Mehrtens JM. 1987. Living Snakes of the World in Color. New York: Sterling Publishers. 480 pp. ISBN 0-8069-6460-X.
5. ^ U.S. Navy. 1991. Poisonous Snakes of the World. US Govt. New York: Dover Publications Inc. 203 pp. ISBN 0-486-26629-X.
6. ^ "Dr. Bryan Grieg Fry: Viper Research". http://www.venomdoc.com/viper.html. Retrieved 2006-04-21.
7. ^ "Studies on venom and venom apparatus of Fea's viper, Azemiops feae.". http://www.ncbi.nlm.nih.gov/ . Retrieved 2006-04-21.

Further reading

* Boulenger GA. 1888. An account of the reptilia obtained in Burma, north of Tenasserium, by ML Fea, of the Genoa Civic Museum. Annali dell Museo Civico di Storia Naturale di Genova (2)6: 593-604[602].
* Boulenger GA. 1893-1896. Catalogue of the Snakes of the British Museum (Natural History). Vol I (1893), Containing the families Typhlopidae, Glauconiidae, Boidae, Ilysiidae, Uropeltidae, Xenopeltidae, Colubridae Aglyphae, part., xiii, 448 pp., 28 pls.; Vol. III (1896), Containing the Colubridae (Opisthoglyphae and Proteroglyphae), Amblycephalidae, and Viperidae, 727 pp., 25 pls. Trustees of the British Museum, London.
* Liem KF, Marx H, Rabb GB. 1971. The viperid snake Azemiops: Its comparative cephalic anatomy and phylogenic position in relation to Viperinae and Crotalinae. Fieldiana: Zoology. Chicago. 59: 67-126.
* Kardong KV. 1986. Observations on live Azemiops feae, Fea’s viper. Herpetological Review 17(4) 81-82.
* Mara WP. 1993. Venomous Snakes of the World. TFH Publications. 275 pp. ISBN 0-86622-522-6.
* Marx H, Olechowski TS. 1970. Fea's viper and the common gray shrew: a distribution note on predator and prey. Journal of Mammology 51:205.
* Mebs D, Kuch U, Meier J. 1994. Studies on venom and venom apparatus of Feae's viper, Azemiops feae. Toxicon 32(10):1275-8.
* Orlov N. 1997. Viperid snakes (Viperidae Bonaparte, 1840) of Tam-Dao mountain range. Russian Journal of Herpetology 4(1):67-74.
* Zhao R. Er-Mi TH, Zhao G. 1981. Notes on Fea's viper from China. Acta Herpetologica Sinica 5(11):66-71.