*** Welcome to piglix ***

? Nycticebus linglom

 ? Nycticebus linglom
Temporal range: ~18 mya
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Suborder: Strepsirrhini
Family: Lorisidae
Genus: Nycticebus (?)
Species: N. (?) linglom
Binomial name
Nycticebus linglom
Mein and Ginsburg, 1997

Nycticebus linglom is a fossil strepsirrhine primate from the Miocene of Thailand. Known only from a single tooth, an upper third molar, it is thought to be related to the living slow lorises (genus Nycticebus), but the material is not sufficient to assign the species to Nycticebus with certainty, and the species name therefore uses open nomenclature. With a width of 1.82 mm, this tooth is very small for a primate. It is triangular in shape, supported by a single root, and shows three main cusps, in addition to various crests. The absence of a fourth cusp, the hypocone, distinguishes it from various other prosimian primates.

Nycticebus linglom was described in 1997 by French paleontologists Pierre Mein and Léonard Ginsburg in a report on the fossil mammals of Li Mae Long, a Miocene site in Thailand. The animal is known from a single tooth, and on the basis of comparisons with other prosimian primates Mein and Ginsburg concluded that it is most closely related to the living slow lorises (genus Nycticebus). However, in view of the very limited material, they only tentatively assigned the fossil species to Nycticebus, using open nomenclature. The specific name, linglom, is the Thai word for "loris".

The single known tooth, a third upper molar (M3) known as T Li 41, is tiny, with a length of 1.29 mm and width of 1.82 mm. Mein and Ginsburg claim that it is the smallest known prosimian molar. The tooth is triangular in shape and shows a simple, reduced morphology. Three important cusps—the , paracone, and metacone—are present, connected by a crest. They are low and rounded. The metacone, located at the back of the tooth, is closer to the protocone, which is on the front lingual corner (the side of the tongue), than it is to the paracone on the front labial corner (the side of the cheeks). The protocone is rounded on the lingual side and is attached to a weak crest on the front and back. On the front labial corner, a lengthy crest, the parastylar crest, is present, which includes a minor cusp known as a parastyle. Some wear is visible on the parastylar crest, and at the front of the tooth a contact facet with the preceding second upper molar is present. The tooth has a single, well-developed root, which contains a number of grooves, suggesting that it consists of three smaller, fused rootlets.


...
Wikipedia

...