Boa constrictor

Binomial name :Boa constrictor (Linnaeus, 1758)

Scientific classification
Kingdom : Animalia
Phylum : Chordata
Class : Reptilia
Order : Squamata
Suborder : Serpentes
Family : Boidae
Subfamily : Boinae
Genus : Boa
Species : B. constrictor

Description and habitat
Though sometimes impressively large, boa constrictors are not the giant snakes of the popular imagination. Depending on their geographic origin and sex (females are usually somewhat larger), they can reach from 3.25 to 13 feet as adults. Boa constrictors have a pattern of brown, reddish-brown to black "saddles" or dorsal blobs of color on a lighter background which can range through white, golden, grey or brownish, pink. Specimens from most localities have more or less prominent dark red, reddish brown or brown markings on the tail.Their preferred habitat is in rain forests and open savannas.Female boas produce live offspring instead of laying eggs. Fertilization by the male is internal. During copulation, males can cling to the female via a small set of "spurs" that are generally hidden below scales on either side of the vent and are actually evolutionary remnants of the hind legs. The gestation period of boas is 108 days after the post ovulation shed.

Subspecies
Amaral's Boa, Boa constrictor amarali (Stull, 1932); Common Red-tailed Boa, Boa constrictor constrictor (Linnaeus, 1758); Common Northern Boa, Boa constrictor imperator (Daudin, 1803); Tumbes Peru Boa, Boa constrictor longicauda (Price&Russo, 1991); Ecuadorian Boa, Boa constrictor melanogaster (Langhammer, 1983); Dominican Clouded Boa, Boa constrictor nebulosa (Lazell, 1964); Argentine Boa, Boa constrictor occidentalis (Philippi, 1863); St. Lucia Boa, Boa constrictor orophias (Linnaeus, 1758); Orton's Boa, Boa constrictor ortonii (Cope, 1878); Pearl Island Boa, Boa constrictor sabogae (Barbour, 1906)

Ecology
The boa constrictor's diet ranges from small rodents and lizards to large birds, marmosets, coatimundi, iguana and opossums. They locate prey by scent but are generally considered opportunistic eaters, preferring to ambush rather than hunt. This is, however, not true for all species; the Puerto Rican Boa will hang in the mouths of caves snatching bats as they fly by. Unlike pythons, they do not have heat sensitive scales on their snout. Also, boas give birth to live young and do not lay eggs like pythons do.

In captivity
Boa constrictors do well in captivity, usually becoming quite tame, and are a common sight in zoos. They can live up to 20 to 30 years old in captivity, with rare accounts of over 40 years old, making them a long-term commitment as a pet. Animal husbandry is the most significant factor in captive lifespan.

While still imported in significant numbers, boa constrictors are widely bred in captivity, both for the casual pet trade and among serious herpetocultural hobbiests. In addition to normal-appearing specimens, animals exhibiting a wide variety of color and pattern mutations (e.g. albinism) are being produced. Many of these are quite expensive.

The subspecies most readily available commercially is B. c. imperator, often termed the "common boa" or "Colombian redtail boa," even though its tail markings tend toward brown rather than the deep red or reddish brown of the "true redtail" subspecies, B. c. constrictor. B. c. imperator is a wide-ranging subspecies and its appearance varies greatly with location. Mainland specimens from Colombia can be among the larger boas, but this subspecies also includes a number of dwarf insular populations, such as those from various Caribbean islands and the Sonoran desert of Mexico. These populations represent the smallest of the boa constrictors.
In recent years many herpetoculurists, mostly working with B. c. imperator, have dedicated themselves to the reproduction of animals with unusual and sometimes spectacular color and pattern mutations, referred to as "morphs" within the hobby. Specimens with anomalous appearance crop up from time to time among imports, or in captive bred animals. When this occurs, breeders will attempt to breed the animal to its own close relations, often its own offspring. If the issue of these breedings show the same traits, then the trait has been "proven" to be an inheritable genetic mutation. Often breeding programs are established to combine more than one mutation, producing even more unusual-looking animals that would never be seen in nature.