My watch list

Agkistrodon bilineatus

Agkistrodon bilineatus

Near Threatened (IUCN)

Scientific classification

Kingdom:	Animalia
Phylum:	Chordata
Subphylum:	Vertebrata
Class:	Reptilia
Order:	Squamata
Suborder:	Serpentes
Family:	Viperidae
Subfamily:	Crotalinae
Genus:	Agkistrodon
Species:	A. bilineatus

Binomial name

Agkistrodon bilineatus
Günther, 1863

Range map for A. bilineatus. Dark blue = A. b. bilineatus, red = A. b. howardgloydi, green = A. b. russeolus, light blue = A. b. taylori.

Synonyms

Ancistrodon bilineatus - Günther, 1863
Ankistrodon bilineatum - Müller, 1877
Tr[igonocephalus] bilineatus - Müller, 1878
Ancistrodon bilineatum - Dugès, 1896
Agkistrodon bilineatus - Stejneger, 1899
Ancistrodonus bilineatus - Herrera, 1899
Agkistrodon bilineatus bilineatus - Burger & Robertson, 1951
Arkistrodon bilineatus - Martín del Campo, 1953
Trigonocephalus specialis - Recinos, 1954
Agkistrodon b[ilineatus]. bilineatus - Lucas, Dupaix-Hall & Biegler, 1972^[1]

Common names: cantil,^[2]^[3] common cantil,^[4] Mexican moccasin,^[3] more.

Agkistrodon bilineatus is a venomous pitviper species found in Mexico and Central America as far south as Costa Rica.^[1] Four subspecies are currently recognized, including the nominate subspecies described here.^[5]

Additional recommended knowledge

Correct Test Weight Handling Guide: 12 Practical Tips

Weighing the right way

Description

These are heavy bodied snakes, and share the same general body structure with cottonmouths. They average around 60 cm in length and have a broad, triangular shaped head with small eyes that have vertical pupils.

Coloration can vary, but most are brown or black, with darker brown or black banding, sometimes with white or cream colored accents. A. taylori is known for being more elaborately patterned, often having distinct tan colored banding, sometimes with orange or yellow accents that can almost appear gold in color. Juveniles of both species are almost always distinctly banded, with a bright green or yellow tip to their tail, which they use to lure prey with. As they age, their pattern and coloration fades and darkens.

Common names

Cantil,^[2]^[3] common cantil,^[4] Mexican moccasin,^[3] tropical moccasin,^[6] Mexican cantil.^[7]

Geographic range

Mexico and Central America. On the Atlantic side it is found in Mexico in Tamaulipas, Nuevo León, possibly northern Veracruz and Chiapas (in the Middle Grijalva Valley). On the Yucatan Peninsula it occurs in Campeche, Yucatán, Quintana Roo and northern Belize. On the Pacific side it is found from southern Sonora in Mexico south through Guatemala, El Salvador, Honduras and Nicaragua to southwestern Costa Rica. On the Pacific side the distribution is almost continuous, while on the Atlantic side it is disjunct. The type locality given is "Pacific coast of Guatemala."^[1]

Conservation status

This species is classified as Near Threatened (NT) on the IUCN Red List of Threatened Species (v3.1, 2001).^[8] A species is listed as such when it has been evaluated against the criteria but does not qualify for Critically Endangered, Endangered or Vulnerable now, but is close to qualifying for, or is likely to qualify for a threatened category in the near future. The population trend is down. Year assessed: 2007.^[9]

The primary ecological concern is habitat loss.

Behavior

Much like the American cottonmouth, this species has a reputation for having a nasty disposition and being extremely dangerous, a reputation probably not well deserved. They are shy by nature, and if threatened their first instinct is usually to flee. If unable to flee they will threat display by raising their head and sometimes opening their mouth. They generally will only strike if given no other choice.

Reproduction

Breeding occurs in the spring, and like most other viper species, cantils are ovoviviparous, giving birth to 5-20 young at a time.

Captivity

Export from Mexico is not permitted, but cantils of both species are often captive bred, making them frequently available in the exotic pet trade. They are also well represented in zoos throughout North America and Europe.

Venom

The venom is considered medically significant to humans. Instituto Clodomiro Picado, in Costa Rica, manufactures a polyvalent antivenin.

Subspecies

Subspecies^[5]	Authority^[5]	Common name^[2]	Geographic range^[2]
A. b. bilineatus	Günther, 1863	Cantil	The Pacific Coastal Plain from southern Sonora in Mexico, southeast to Guatemala and El Salvador. Also occurs in the Mexican state of Morelos.
A. b. howardgloydi	Conant, 1984	Castellana	The dry Pacific lowlands of Honduras, Nicaragua and Costa Rica.
A. b. russeolus	Gloyd, 1972	Yucatecan cantil	The Yucatán Peninsula in Mexico in the states of Campeche, Quintana Roo and Yucatán, as well as in northern Belize.
A. b. taylori	Burger & Robertson, 1951	Taylor's cantil	Mexico, in the northeastern states of Nuevo Leon, San Luis Potosí and Tamaulipas.

Taxonomy

A new subspecies, A. b. lemosespinali, was described by Smith and Chiszar (2001) based on a single specimen from near Palma Sola, Veracruz, Mexico.^[10]

References

^ ^a ^b ^c 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).
^ ^a ^b ^c ^d Gloyd HK, Conant R. 1990. Snakes of the Agkistrodon Complex: A Monographic Review. Society for the Study of Amphibians and Reptiles. 614 pp. 52 plates. LCCN 89-50342. ISBN 0-916984-20-6.
^ ^a ^b ^c ^d Mehrtens JM. 1987. Living Snakes of the World in Color. New York: Sterling Publishers. 480 pp. ISBN 0-8069-6460-X.
^ ^a ^b Campbell JA, Lamar WW. 2004. The Venomous Reptiles of the Western Hemisphere. Comstock Publishing Associates, Ithaca and London. 870 pp. 1500 plates. ISBN 0-8014-4141-2.
^ ^a ^b ^c Agkistrodon bilineatus (TSN 585702). Integrated Taxonomic Information System. Accessed on 2 November 2006.
^ Gotch AF. 1986. Reptiles -- Their Latin Names Explained. Poole, UK: Blandford Press. 176 pp. ISBN 0-7137-1704-1.
^ Parker HW, Grandison AGC. 1977. Snakes -- a natural history. Second Edition. British Museum (Natural History) and Cornell University Press. 108 pp. 16 plates. LCCCN 76-54625. ISBN 0-8014-1095-9 (cloth), ISBN 0-8014-9164-9 (paper).
^ Agkistrodon bilineatus at the IUCN Red List. Accessed 13 September 2007.
^ 2001 Categories & Criteria (version 3.1) at the IUCN Red List. Accessed 13 September 2007.
^ Smith HM, Chiszar D. 2001. A new subspecies of cantil (Agkistrodon bilineatus) from Central Veracruz, Mexico (Reptilia: Serpentes). Bulletin of the Maryland Herpetological Society, 37: 130-136.

Category: Crotalinae

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Agkistrodon_bilineatus". A list of authors is available in Wikipedia.