Casarea

Taxobox
name = "Casarea"

---

status = EN
status_system = iucn2.3
regnum = Animalia
phylum = Chordata
subphylum = Vertebrata
classis = Reptilia
ordo = Squamata
subordo = Serpentes
familia = Bolyeriidae
genus = "Casarea"
genus_authority = Gray, 1842
species = "C. dussumieri"
binomial = "Casarea dussumieri"
binomial_authority = (Schlegel, 1837)
synonyms = * "Casarae" - Gray, 1842
* "Leptoboa" - A.M.C. Duméril & Bibron, 1844McDiarmid 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).] ----
* "B" ["oa"] . "dussumiri" - Schlegel, 1837 (typographical error)
* "Boa Dussumieri" - Schlegel, 1837
* "Boa Dussumieri" - Gray, 1842
* "Casarea dussumieri" - Gray, 1842
* "Leptoboa dussumieri" - Duméril & Bibron, 1844
* "Casarea dussumieri" - Boulenger, 1893

:"Common names: Round Island boa,ITIS|ID=202190|taxon="Casarea dussumieri"|year=2007|date=16 August] Round Island keel-scaled boa. [http://www.iucnredlist.org/search/details.php/3989/all "Casarea dussumieri"] at [http://www.iucnredlist.org/ IUCN Red List] . Accessed 16 August 2007.] "Casarea is a monotypic genusITIS|ID=202189|taxon="Casarea"|year=2007|date=16 August] created for the species "C. dussumieri", which is endemic to Round Island. No subspecies are currently recognized.

Description

Adults are slender and reach a maximum length of 150 cm (5 ft). The males have slimmer, more pointed heads and have shorter bodies than the females. The body is covered in small keeled scales that give the species its common name. The genus is unique among vertebrates as it has a split jaw (intramaxilliary joint that separates anteria and posteria bones); an adaptation that may be advantageous in catching its main prey of geckos and skinks.

The color pattern is dark brown dorsally, the belly being lighter with dark spots. Over a 24 hour period the boa has a shift in color, changing from ‘dark’ during its relatively inactive day time period to ‘light’ in the early evening through to dawn when it is most active. This effect is created through polychromatic skin cells.

Geographic range

Mauritius. Currently known only to survive on Round Island, but previously recorded on the islands of Gunner's Quoin, Flat Island, mainland Mauritius (subfossil remains) and Ile de la Pas. The type locality given is "I'île ronde, près de Maurice" (Round Island, Mauritius).

Conservation status

This species is classified as Endangered (E) on the IUCN Red List for the following criteria: D (v2.3, 1994). This means that, although it is not Critically Endangered, it is is facing a very high risk of extinction in the wild in the near future because the population is estimated to number less than 250 mature individuals. Year assessed: 1996. [http://www.iucnredlist.org/info/categories_criteria1994#categories 1994 Categories & Criteria (version 2.3)] [http://www.iucnredlist.org/ IUCN Red List] . Accessed 16 August 2007.]

Recent conservation efforts have seen an increase in the number of adult boas to around 1000. This has been achieved by eradicating goats and rabbits from the island and restoring natural habitat which has led to an increase of the boas’ natural pray.

Reproduction

Breeding begins during April, although young have been observed throughout the year. A clutch of up to 12 soft shelled eggs can be laid amongst leaf litter or in hollow palm trunks, and is sometimes attended by the female. Incubation is unusually long for a snake, lasting about 90 days. The young are born bright orange in color and weigh less than 5 grams.

ee also

*
*

References

Further reading

* McAlpine, DF. 1981. Activity Patterns of the Keel-Scaled Boa ("Casarea dussumiera") at the Jersey Wildlife Preservation trust. Dodo, Journal of the Jersey Wildlife Preservation trust 18:74-78.
* Bloxam, QMC. 1984. A preliminary report on the captive management and reproduction of the Round Island Boa, "Casarea dussumieri". Proceeding of 7th Annual Reptile Symposium on Captive Propagation and Husbandry, 155-177, ed. by P. Tolson, Zool. Consortium Inc., Thurmont Maryland.

External links

*
* [http://www.arkive.org/species/GES/reptiles/Casarea_dussumieri/more_info.html Round Island keel-scaled boa ("Casarea dussumieri")] at [http://www.arkive.org/ ARKive] . Accessed 18 February 2008.
* [http://www.encyclopedia.mu/Nature/Fauna/Reptiles/Casarea_dussumieri.htm Keel Scaled Round Island boa] at [http://www.encyclopedia.mu/ The Mauritian Encyclopedia] . Accessed 18 February 2008.
* [http://www.nationalgeographic.com/wildworld/profiles/terrestrial/at/at0120.html Mascarene forests] at [http://www.nationalgeographic.com/ National Geographic] . Accessed on 18 February 2008.