Macroscincus

Macroscincus coctei
The extinct Cape Verde giant skink
Conservation status

Extinct  (2013)  (IUCN 3.1)[1]
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Reptilia
Order: Squamata
Suborder: Sauria or
Lacertilia
Infraorder: Scincomorpha
Family: Scincidae
Genus: Macroscincus
Species: M. coctei
Binomial name
Macroscincus coctei
(A.M.C. Duméril & Bibron, 1839)
Synonyms
  • Euprepes coctei
    A.M.C. Duméril & Bibron, 1839
  • Macroscincus coctei
    Boulenger, 1887
  • Gongylus coctei
    — Frank & Ramus, 1995
  • Macroscincus coctei
    Andreone & Gavetti, 1998
  • Chioninia coctei
    Miralles et al., 2010[2]

Macroscincus coctei, also called the Cape Verde giant skink, lagarto, or Cocteau's skink, is a species of lizard, a reptile that was at one time known to inhabit the islets of Branco and Raso in the Cape Verde islands of the Atlantic Ocean, rendered deserts by human-caused habitat destruction. No Macroscincus coctei has been observed since early in the 20th century.

Etymology

The specific name, coctei, is in honor of French physician and zoologist Jean Théodore Cocteau (1798-1838).[3]

Description

M. coctei was very large for a skink. Adults could attain a snout to vent length (SVL) of 32 cm (13 in),[4] and the cylindrical tail was as long as the head and body.[5]

Decline of population

Causes cited for their decline include over hunting for food and use for "skink oil" by natives of neighboring islands and prolonged drought. At one time, starving convicts were marooned in the Cape Verde archipelago and ate the extant population of Macroscincus coctei. An explorer, Leonardo Fea, brought back several specimens which are now housed in Italy. This constitutes the extant specimens of Macroscincus coctei. Subsequent explorers such as Sheliech, Andreone, and Pather, have failed to find living Macroscincus. In the early 20th century, German herpetologists tried to captive-breed this species to no avail.

In the 2013.1 version of the IUCN Red List, the IUCN declared the Macroscincus officially extinct.[6][7]

Biology

Macroscincus was largely herbivorous, but whether out of necessity with deteriorating conditions or from opportunistic advantage, occasionally became more carnivorous as individuals would occasionally eat the young from nesting shore birds. German herpetologists had noted Macroscincus consuming birds in captivity in the early 20th century.

One interesting aspect of this species is that it possessed a transparent lower eyelid; possibly to spot predators from below.

From the examination of preserved specimens, it appears that this species had a "belly button" slit, indicating viviparism. However, there are also reports that indicate this species was an egg layer.

Macroscincus is considered unique among the Scincidae in having tooth crowns which are labiolingually compressed and multicuspate.[4]

It has been found through mitochrondrial DNA sequences that Macroscincus coctei was most closely related to the Mabuya genus of the Scincidae and may have constituted a clade.[8]

Macroscincus coctei had a SENI value of 0.13.[9] As such, it was a low arboreal skink that was borderline enough to adapt to the semi-desert like conditions created when the Cape Verde islands were denuded by humans and domesticated animals centuries ago.

References

  1. Vasconcelos R. (2013). Chioninia coctei. The IUCN Red List of Threatened Species. Version 2014.2.
  2. The Reptile Database. www.reptile-database.org.
  3. Beolens B, Watkins M, Grayson M. 2011. The Eponym Dictionary of Reptiles. Baltimore: Johns Hopkins University Press. xiii + 296 pp. ISBN 978-1-4214-0135-5. (Macroscincus coctei, p.56).
  4. 4.0 4.1 Greer, A. E. (1976). "On the evolution of the giant Cape Verde scincid lizard Macroscincus coctei". Journal of Natural History 10 (6): 691. doi:10.1080/00222937600770551.
  5. Boulenger GA. 1887. Catalogue of the Lizards in the British Museum (Natural History). Second Edition. Volume III. ... Scincidæ ... London: Trustees of the British Museum (Natural History). (Taylor and Francis, printers). xii + 575 pp. + Plates I-XXVII. (Macroscincus coctei, p. 149).
  6. "News – World’s oldest and largest species in decline – IUCN Red List". Iucnredlist.org. 2013-07-02. Retrieved 2013-11-26.
  7. "Macroscincus coctei (Cape Verde Giant Skink, Cocteau's Skink)". Iucnredlist.org. 1996-08-01. Retrieved 2013-11-26.
  8. Carranza, S; Arnold, E. N.; Mateo, J. A.; López-Jurado, L. F. (2001). "Parallel gigantism and complex colonization patterns in the Cape Verde scincid lizards Mabuya and Macroscincus (Reptilia: Scincidae) revealed by mitochondrial DNA sequences". Proceedings of the Royal Society B: Biological Sciences 268 (1476): 1595–603. doi:10.1098/rspb.2001.1699. PMC 1088783. PMID 11487407.
  9. Schnirel, Brian L.; 2004. SENI biometric analysis on the extinct Scincidae species: Macroscincus coctei. Polyphemos, Volume 1, Issue 2, May, Florence, South Carolina, U.S.A. pp. 12–22.

Bibliography