Drymarchon melanurus erebennus

Texas Indigo Snake
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	Squamata
Family:	Colubridae
Subfamily:	Colubrinae
Genus:	Drymarchon
Species:	D. melanurus
Subspecies:	D. m. erebennus
Trinomial name
Drymarchon melanurus erebennus Cope, 1860
Synonyms
Drymarchon corais erebennus

The Texas Indigo Snake (Drymarchon melanurus erebennus) is a large, nonvenomous, colubrid snake found from southern Texas south into Mexico as far as Veracruz.

Description

Texas Indigo Snakes are predominantly black in color, with a high sheen which gives their scales an amazing iridescence. Their underside is often a salmon pink color. They are large snakes, regularly attaining lengths beyond 6 ft (1.8 m); 8 ft (2.4 m) long specimens are not unheard of.

Habitat

Texas Indigo Snakes prefer lightly vegetated areas not far from permanent water sources, but are also found in mesquite savannah, open grassland areas, and coastal sand dunes. They den in burrows left by other animals.

Behavior and diet

Indigo snakes are diurnal snakes, and spend most of their time actively foraging for prey. They will consume almost anything they can overpower and swallow, including mammals, birds, lizards, frogs, turtles, eggs, and even other snakes, including rattlesnakes. Because of its aggressive attacks on rattlesnakes, many farmers in southern Texas consider it a useful ally.^[1] Hence the adage, "If it's an Indigo, let it go." They are not a typically aggressive snake, but may bite or release a foul smelling musk from its cloaca if handled or harassed. Like many colubrid snakes, it will often shake its tail as a warning - even though it does not possess a rattle.

Reproduction

Breeding takes place, generally yearly, in the winter. Clutches that average 10-12 eggs are laid in the spring, and hatch around 80 days later. Hatchlings can be up to 26 in (66 cm) long. Maturity is reached in 2-3 years.

Conservation

The Texas Indigo Snake is listed as a threatened species by the state of Texas. Its primary threat is from habitat loss due to human development. Each snake requires a large home range to forage, and urban sprawl is shrinking their usable habitat. Roads bisect their territory, and many snakes each year are run over by cars.

References

1. ^ Werler, John E. & Dixon, James Ray, ed (2000). "Texas Indigo Snake (Erebennus, Drymarchon C.)". Texas snakes: identification, distribution, and natural history. University of Texas Press. p. 101. ISBN 9780292791305. http://books.google.com/books?id=7jKuAWavrUkC&pg=PA101. 

Further reading

• Herps of Texas: Drymarchon corais erebennus
• Texas Indigo Snake
• Werler, J.E. and J.R. Dixon. 2000. Texas snakes: identification, distribution, and natural history. University of Texas Press Austin, Texas. pp 98-102.
• Integrated Information Taxonomic System: Drymarchon melanurus erebennus.
• Crother, B.I., J. Boundy, J.A. Campbell, K. de Quieroz, D. Frost, D.M. Green, R. Highton, et al. 2003. Scientific and standard English names of amphibians and reptiles of North America north of Mexico: Update. Herpetological Review 34: 196-203.