''Sectisodon'' ("cutting tooth") is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

of hyainailourid hyaenodont mammal of the

polyphyletic A polyphyletic group is an assemblage of organisms or other evolving elements that is of mixed evolutionary origin. The term is often applied to groups that share similar features known as homoplasies, which are explained as a result of conver ...

tribe

Hyainailourini Hyainailourini ("hyena-cats") is an extinct polyphyletic tribe of hyainailourid hyaenodonts from paraphyletic subfamily Hyainailourinae that lived in Africa, Asia and Europe during the middle Eocene to middle Miocene. Classification and phylo ...

within

paraphyletic In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be pa ...

subfamily

Hyainailourinae Hyainailourinae ("hyena-cats") is an extinct paraphyletic subfamily of hyainailourid hyaenodonts that lived in Africa, Asia, North America and Europe during the middle Eocene to middle Miocene. Classification and phylogeny Taxonomy * Subfami ...

from early

Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but ...

to early

Miocene The Miocene ( ) is the first 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 means "less recent" ...

deposits in

Egypt Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia via a land bridge formed by the Sinai Peninsula. It is bordered by the Med ...

and

Uganda }), is a landlocked country in East Africa. The country is bordered to the east by Kenya, to the north by South Sudan, to the west by the Democratic Republic of the Congo, to the south-west by Rwanda, and to the south by Tanzania. The south ...

Description

Morales and Pickford (2017, p. 346) diagnose ''Sectisodon'' as follows: "Hyainailourinae of small dimensions, M1 and M2 of similar length. M2 with paracone and metacone fused together, tall and pointed. Protocone very reduced, flattened and extending basally beyond the base of the paracone. Anterior cingulum with a well-defined parastyle with a moderate buccal cingulum. M2 and M1 with the metastyle quite a bit longer than the paracone-metacone. P3 short, with tall main cusp, posterior cusplet moderate, and much reduced protocone. Basal lingual cingulum strong, weaker on the buccal side. Lower molars with protoconid bigger than the metaconid, m2 with talonid present, much reduced in the m3."

Classification and phylogeny

Taxonomy

''Sectisodon markgrafi'' was originally assigned to genus '' Metapterodon'' by Holroyd (1999), who nonetheless recognized that Eocene and Oligocene hyainailourids he assigned to ''Metapterodon'' might prove generically distinct. Subsequent study demonstrated referred ''M. markgrafi'' to ''Sectisodon'' based on shared similarities with ''S. occultus''.

Phylogeny

The phylogenetic relationships of genus ''Sectisodon'' are shown in the following cladogram:

References

Hyaenodonts Oligocene mammals of Africa Miocene mammals of Africa Fossil taxa described in 2017 Prehistoric placental genera {{paleo-mammal-stub