Plesiorycteropus
Plesiorycteropus, also known as the bibymalagasy or Malagasy aardvark, is a recently extinct genus of mammals from Madagascar. Upon its description in 1895, it was classified with the aardvark, but more recent molecular evidence instead suggests that it is most closely related to the tenrecs (a group extant on the island). Two species are currently recognized, the larger P. madagascariensis and the smaller P. germainepetterae. They probably overlapped in distribution, as subfossil remains of both species have been found in the same site.
Knowledge of the skeletal anatomy is limited, as only limb, partial pelvis, and skull bones have been recovered to date. Plesiorycteropus was probably a digging animal that fed on insects such as termites and ants. It also shows adaptations for climbing and sitting. Estimates of its mass range from 6 to 18 kilograms (13 to 40 lb). When and why it became extinct remains unknown. One bone has been radiocarbon dated to 200 BCE; forest destruction by humans may have contributed to its extinction.
French naturalist Henri Filhol first described Plesiorycteropus madagascariensis in 1895 on the basis of a partial skull found at the cave of Belo. His description was vague even by 19th-century standards, but he placed the animal close to the aardvark (Orycteropus).[4] The generic name combines Ancient Greek plesio- "near" with Orycteropus, the genus of the aardvark, and the specific name refers to Madagascar. Charles Lamberton, who had access to a larger sample for his 1946 review of the genus, noted substantial variation, but did not attempt to differentiate multiple species.[3] In 1994, Ross MacPhee again reviewed Plesiorycteropus and was able to separate two species, the larger P. madagascariensis and a new, smaller species that he named Plesiorycteropus germainepetterae after scientist Germaine Petter. The two species differ in a number of morphological characters in addition to size.[1]
Remains of Plesiorycteropus have been misidentified as rodents and primates. Charles Immanuel Forsyth Major described Myoryctes rapeto in 1908 as a "giant subfossil rat" on the basis of two innominate bones (pelvic bones).[5] The generic name was replaced by Majoria in 1915, because Myoryctes was preoccupied by the name of a nematode worm.[6] However, according to MacPhee, innominates of Majoria are identical to those assigned to Plesiorycteropus. Guillaume Grandidier assigned a well-preserved femur (upper leg bone) to a gigantic relative of the living votsovotsa (Hypogeomys antimena), a large rodent, which he described as Hypogeomys boulei. Lamberton identified this femur as Plesiorycteropus and MacPhee concurred.[7] Remains of both Majoria rapeto and Hypogeomys boulei fall at the upper end of the size range of the genus, indicating that they are referable to P. madagascariensis.[1] Another Plesiorycteropus innominate was mistakenly assigned to Daubentonia robusta, the extinct giant aye-aye,[8] and other material has been misidentified as of a dwarf lemur (Cheirogaleus).[9]
