Dermotherium

In addition, a single isolated upper molar from the Early Oligocene of Pakistan has been tentatively assigned to D. chimaera.

[2] In that year, Stéphane Ducrocq and colleagues described a jaw fragment from the Eocene of Thailand as a new genus and species of colugo, Dermotherium major.

[4] Mary Silcox and colleagues reaffirmed the colugo affinities of Dermotherium in 2005 on the basis of detailed similarities in molar morphology.

[7] According to a phylogenetic analysis carried out by Marivaux and colleagues, D. chimaera, D. major, and the Myanmar dermopteran are successive sister groups of the two living colugos.

The coronoid process (a projecting piece of bone directly behind the molars) rises steeply, with its front wall virtually vertical.

[9] The i3 of Dermotherium chimaera is an elongate tooth bearing six tines (narrow, high "fingers" as in a comb) arranged from front to back.

[19] The pectinate (comb-like) shape of the anterior teeth is a shared characteristic of the colugos and highly unusual among mammals.

[21] In Dermotherium chimaera, the p4 and m1 through m3 are similar to each other (and unlike the i3, canine, and p3) and appear to form a series of decreasing size from front to back.

[23] Although a crest, the postmetacristid, descends from the back side of the metaconid, ending in a small cusp, the metastylid, it is separated from the entoconid by a notch.

[11] In D. chimaera, a low crest, the post-hypoconulid cristid, reaches from the hypoconulid to the back lingual corner of the tooth, where a small cuspule, the distocuspid, is located.

[11] The upper molars of Dermotherium chimaera are triangular in overall shape and much broader than long, with the narrow end of the triangle pointing lingually.

[26] The crest in front of and behind the major cusps on the buccal side of the tooth, the paracone and metacone, are well-developed, together forming a long W-shaped ridge.

[11] The enamel is wrinkled on the flanks of the paracone and metacone and, in the Thai but not the Pakistani specimens, on the lingual side of the protocone.

[27] Dermotherium major was found in a lignite pit known as Wai Lek in Krabi Province, southwestern Thailand.

[31] It is part of the Krabi Basin fauna, which contains at least 40 mammalian genera, mostly artiodactyls but also including some primates, such as Siamopithecus, Wailekia, and Muangthanhinius.

The fossil deposits, located in the Cha Prong pit in a coal mine called Nong Ya Plong, are dated to the Late Oligocene.

[34] Paali Nala, where the M2 tentatively assigned to Dermotherium chimaera was found, is in the Bugti Hills of Balochistan, western Pakistan.

The fossil locality, placed stratigraphically in the Bugti Member of the Chitarwata Formation, is thought to be Early Oligocene in age.

A Sunda colugo ( Galeopterus variegatus ), a living relative of Dermotherium