Eorhynchocyon

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Eorhynchocyon
Temporal range: Bartonian–Priabonian
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Macroscelidea
Family: Rhynchocyonidae
Genus: Eorhynchocyon
Senut & Pickford, 2021
Species:
E. rupestris
Binomial name
Eorhynchocyon rupestris
Senut & Pickford, 2021
Eorhynchocyon resembled extant elephant shrew (as presented Black and rufous elephant shrew) in some traits Elephant Shrew.jpg
Eorhynchocyon resembled extant elephant shrew (as presented Black and rufous elephant shrew) in some traits

Eorhynchocyon is an extinct mammal genus from the macroscelidid superfamily.

Fossils of an unknown animal were found in Namibia. The fossils descended from Bartonian-Priabonian stage. [1]

Authors describe it as a Macroscelidea member of middle size. As a diagnostic trait they enlisted convex mandible profile and ascending mandible ramus leaning backwordly. Mandible shape resembled the elephant shrew, known scientifically as Hypsorhynchocyon . Whole mandible length measures 36 mm and alveolar processes are from 21.4 to 22 mm. In a half of mandible three incisors, one canine, four premolars and two molar was found. [1] Identical dental formula characterises extant elephant shrews. [2] No diastema is present. Lower canine teeth have 2 roots converging partially or completely. [1]

Senut and Pickford named the described genus Eorhynchocyon. First part of the generic name, prefix eo, has Greek origin and means dawn [1] (Greek word eos was used in other taxa names, as Eocarcharia ). [3] Rhyncho denotes muzzle and cyon means dog. [1] Altogether they consist a generic name of modern day mammal Rhynchocyon of common name elephant shrew or sengi. [2] In the genus Eorhynchocyon a singular species was classified, namely Eorhynchocyon rupestris. Holotype is specimen EC7 7.2a, comprising complete left mandible. Type locality is Eocliff 7, Namibia. [1]

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References

  1. 1 2 3 4 5 6 Senut, B.; Pickford, M. (2021). "Micro-cursorial mammals from the late Eocene tufas at Eocliff, Namibia" (PDF). Communications of the Geological Survey of Namibia. 23: 90–160.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  2. 1 2 S. Heritage (2018). "Family Macroscelididae (Sengis)". In R.A. Mittermeier & D.E. Wilson (ed.). Handbook of the Mammals of the World . Vol. 8. Insectivores, Sloths and Colugos. Barcelona: Lynx Edicions. p. 227. ISBN   978-84-16728-08-4.
  3. Paul C. Sereno, Stephen L. Brusatte (2008). "Basal abelisaurid and carcharodontosaurid theropods from the Lower Cretaceous Elrhaz Formation of Niger" (PDF). Acta Palaeontologica Polonica. 53: 15–46. doi:10.4202/app.2008.0102.