The Round Island burrowing boa (''Bolyeria multocarinata'') is an extinct

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

snake Snakes are elongated, Limbless vertebrate, limbless, carnivore, carnivorous reptiles of the suborder Serpentes . Like all other Squamata, squamates, snakes are ectothermic, amniote vertebrates covered in overlapping Scale (zoology), scales. Ma ...

, in the

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ...

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

''Bolyeria'', in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Bolyeriidae :''Common names: Mauritius snakes, Round Island boas, splitjaw snakes.'' The Bolyeriidae are a family of snakes native to Mauritius and a few islands around it, especially Round Island. They also used to be found on the island of Mauritius, but ...

. The species, which was

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

Mauritius Mauritius ( ; french: Maurice, link=no ; mfe, label=Mauritian Creole, Moris ), officially the Republic of Mauritius, is an island nation in the Indian Ocean about off the southeast coast of the African continent, east of Madagascar. It incl ...

, was last seen on Round Island in 1975. There are no recognized

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...

Description

''B. multocarinata'' reached about in total length (including tail). Preserved specimens have been reported as having total lengths of . Its colour was described as light brown with blackish spots

dorsally Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...

, and pink marbled with blackish ventrally. It had a pointed snout with a cylindrical body and head. Its general body form suggests that the Round Island burrowing boa had

fossorial A fossorial () animal is one adapted to digging which lives primarily, but not solely, underground. Some examples are badgers, naked mole-rats, clams, meerkats, and mole salamanders, as well as many beetles, wasps, and bees. Prehistoric eviden ...

tendencies. This species' closest living relative is the Round Island boa (''Casarea dussumieri'').

Geographic range

The Round Island burrowing boa had an extremely small range of only . Its

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

s were hardwood forests and palm savanna. In the past it was found in

on Gunner's Quoin, Flat Island, Round Island, and Ile de la Passe. It survived the longest on Round Island, where it was last recorded. The type locality given is "Port Jackson" (in error).

Habitat

The preferred natural

of ''B. multocarinata'' was

forest A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' ...

Diet

The diet of ''B. multocarinata'' is unknown, but it is thought to have eaten

lizard Lizards are a widespread group of squamate reptiles, with over 7,000 species, ranging across all continents except Antarctica, as well as most oceanic island chains. The group is paraphyletic since it excludes the snakes and Amphisbaenia alt ...

s and their eggs, as well as the chicks and eggs of ground-nesting and burrowing seabirds.

Reproduction

''B. multocarinata'' was

oviparous Oviparous animals are animals that lay their eggs, with little or no other embryonic development within the mother. This is the reproductive method of most fish, amphibians, most reptiles, and all pterosaurs, dinosaurs (including birds), and ...

Clutch A clutch is a mechanical device that engages and disengages power transmission, especially from a drive shaft to a driven shaft. In the simplest application, clutches connect and disconnect two rotating shafts (drive shafts or line shafts). ...

size was about five eggs.

Conservation status

The species ''Bolyeria multocarinata'' is classified as Extinct (EX) on the

IUCN The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

Red List of threatened species (v2.3, 1994). It was already rare by 1949 and was last seen by conservationists in 1974. Reasons for its extinction are habitat loss caused by soil erosion due to

overgrazing Overgrazing occurs when plants are exposed to intensive grazing for extended periods of time, or without sufficient recovery periods. It can be caused by either livestock in poorly managed agricultural applications, game reserves, or nature res ...

by goats and rabbits and heavily persecuted by early settlers. Day, David (1981). ''The Doomsday Book of Animals''. (Foreword by HRH The Duke of Edinburgh). London:

Ebury Press Ebury Publishing is a division of Penguin Random House, and is a publisher of general non-fiction books in the UK. Ebury was founded in 1961 as a division of Nat Mags and was originally located on Ebury Street in London. It was sold to Century ...

. 288 pp.

References

* Boie F (1827). "''Bemerkungen über Merrem's Versuch eines Systems der Amphibien. 1te Lieferung: Ophidier'' ". ''Isis von Oken, Jena'' 20: 508–566. ("''Eryx Multocarinata''", new species, p. 513). (in German). * Boulenger GA (1893). ''Catalogue of the Snakes in the British Museum (Natural History). Volume I., Containing the Families ... Boidæ ...'' London: Trustees of the British Museum (Natural History). (Taylor and Francis, printers). xiii + 448 pp. + Plates I-XXVIII. (Genus ''Bolieria'', pp. 121–122; species ''Bolieria multicarinata'', p. 122). * Gray JE (1842). "Synopsis of the species of prehensile-tailed Snakes, or Family BOIDÆ". ''Zoological Miscellany'' 2: 41–46. (''Bolyeria'', new genus, p. 46). * Jan (1864). ''Iconographie générale des Ophidiens. Troisième livraison'' Thirteenth issue Sordelli.html"_;"title=":fr:Ferdinando_Sordelli.html"_;"title="llustrations_by_:fr:Ferdinando_Sordelli">Sordelli">:fr:Ferdinando_Sordelli.html"_;"title="llustrations_by_:fr:Ferdinando_Sordelli">Sordelli_Paris:_Baillière._Index_+_Plates_I-VI._(''Platygaster_multicarinatus'',_Plate_III)._(in_French). {{Use_dmy_dates.html" ;"title=":fr:Ferdinando_Sordelli">Sordelli.html" ;"title=":fr:Ferdinando_Sordelli.html" ;"title="llustrations by :fr:Ferdinando Sordelli">Sordelli">:fr:Ferdinando_Sordelli.html" ;"title="llustrations by :fr:Ferdinando Sordelli">Sordelli Paris: Baillière. Index + Plates I-VI. (''Platygaster multicarinatus'', Plate III). (in French). {{Use dmy dates">date=August 2019 Bolyeriidae Extinct reptiles Reptile extinctions since 1500 Extinct animals of Mauritius Endemic fauna of Mauritius Reptiles described in 1827 Taxa named by Friedrich Boie Reptiles of Mauritius Species made extinct by human activities