''Miomachairodus'' is an extinct

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of large machairodontine (saber-toothed cat) containing only a single species, ''Miomachairodus pseudailuroides''. It is mainly known from

Middle Miocene The Middle Miocene is a sub-epoch of the Miocene epoch (geology), epoch made up of two Stage (stratigraphy), stages: the Langhian and Serravallian stages. The Middle Miocene is preceded by the Early Miocene. The sub-epoch lasted from 15.97 ± 0. ...

-age

fossils A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

Turkey Turkey, officially the Republic of Türkiye, is a country mainly located in Anatolia in West Asia, with a relatively small part called East Thrace in Southeast Europe. It borders the Black Sea to the north; Georgia (country), Georgia, Armen ...

and persisted until the early

Late Miocene The Late Miocene (also known as Upper Miocene) is a sub-epoch of the Miocene epoch (geology), Epoch made up of two faunal stage, stages. The Tortonian and Messinian stages comprise the Late Miocene sub-epoch, which lasted from 11.63 Ma (million ye ...

(

Vallesian The Vallesian age is a period of geologic time (11.6–9.0 Ma) within the Miocene used more specifically with European Land Mammal Ages. It precedes the Turolian age and follows the Astaracian age. The so-called Vallesian Crisis resulted in th ...

). Fossils of this machairodont have been found in the

-age Bahe Formation in

Shaanxi Shaanxi is a Provinces of China, province in north Northwestern China. It borders the province-level divisions of Inner Mongolia to the north; Shanxi and Henan to the east; Hubei, Chongqing, and Sichuan to the south; and Gansu and Ningxia to t ...

, China, and Yeni Eskihisar in

Anatolia Anatolia (), also known as Asia Minor, is a peninsula in West Asia that makes up the majority of the land area of Turkey. It is the westernmost protrusion of Asia and is geographically bounded by the Mediterranean Sea to the south, the Aegean ...

. This Turkish site is of Miocene age and is well known for its pollen studies.

History and naming

The genus was first named by paleontologist Norbert Schmidt-Kittler in 1976 based on the holotype, a partial skull from Akçaköy, Eşme District, Turkey, and a second specimen, a lower jaw from Yeni Eskihisar. The generic name ''Miomachairodus'' is a combination of ''Mio'', referring to the

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

when it lived, and ''Machairodus''; the specific name ''pseudailuroides'' means "like ''Pseudaelurus''". In 2022, material from the Guanigou fauna in the Linxia Basin was described as ''Miomachairodus'' sp., and the authors suggested that it represented a new species of ''Miomachairodus''. The fossil, a partial maxilla from the early Late Miocene (early Bahean), represented the oldest known machairodontine in Asia. They refrained from definitively naming the species because it lacked the fourth premolar. The fossil material had previously been assigned to ''

Machairodus ''Machairodus'' (from , 'knife' and 'tooth') is a genus of large Machairodontinae, machairodont or ''saber-toothed cat'' that lived in Africa and Eurasia during the Middle Miocene, Middle to Late Miocene, from 12.5 million to 8.7 million years ...

palanderi'' in 2013.

Description

The ''Miomachairodus'' sp. from the Linxia Basin is known only from a single fossil (HMV2039), a partial

maxilla In vertebrates, the maxilla (: maxillae ) is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxil ...

with the first, second, and third

incisor Incisors (from Latin ''incidere'', "to cut") are the front teeth present in most mammals. They are located in the premaxilla above and on the mandible below. Humans have a total of eight (two on each side, top and bottom). Opossums have 18, wher ...

s, the canine, and the third

premolar The premolars, also called premolar Tooth (human), teeth, or bicuspids, are transitional teeth located between the Canine tooth, canine and Molar (tooth), molar teeth. In humans, there are two premolars per dental terminology#Quadrant, quadrant in ...

present, as well as the alveolus of the second premolar and a broken fourth premolar. The incisors are small and the canine tooth has "distinct but small" serrations. It was distinguished from ''M. pseudailuroides'' by having a shorter

diastema A diastema (: diastemata, from Greek , 'space') is a space or gap between two teeth. Many species of mammals have diastemata as a normal feature, most commonly between the incisors and molars. More colloquially, the condition may be referred to ...

between the canine and third premolar, and in the differing morphology of the third premolar. The describing paper estimated it was a large carnivoran that weighed more than .

Classification

A 2018 phylogenetic analysis recovered ''Miomachairodus pseudailuroides'' as basal to most of the rest of Machairodontinae.

History and naming

Description

Classification

References

Further reading