New Amphicyonids (Mammalia, Carnivora) from Moghra, Early Miocene, Egypt

Abstract

We describe two large amphicyonid (Amphicyonidae, Carnivora) mandibles from Moghra, Early Miocene, Egypt. One of these represents a new species of Cynelos Jourdan, 1862, which is in the same size range as C. macrodon (Savage, 1965) and C. ginsburgi n. comb., but exhibits a relatively longer m1 paraconid blade. The other is allocated to Amphicyon giganteus (Schinz, 1825). Based on this new material the differences between Cynelos, Amphicyon Lartet in Michelin, 1836, and Afrocyon Arambourg, 1961 are clarified. We also reassign three (P4, M1, M2) of four isolated and unas-GEODIVERSITAS • 2019 • 41 (21) Morlo M. et al. sociated amphicyonid teeth from Moghra, previously attributed to "Cynelos sp. nov." to Amphicyon giganteus. These teeth represent the first record of the upper dentition of A. giganteus from Africa. Enhanced diagnoses of Cynelos and Amphicyon also permit the reallocation of some other previously described specimens to these taxa. These include: assignment of "Amphicyon sp." and an isolated m2 previously identified as "Afrocyon burolleti Arambourg, 1961" from Gebel Zelten, Libya, to the new species of Cynelos; allocation of "Ysengrinia" ginsburgi from Arrisdrift, South Africa, to Cynelos ginsburgi n. comb.; and attribution of a giant undescribed additional species from Buluk, Kenya to Cynelos sp. Other specific specimens from Gebel Zelten and Kenya, currently assigned to Afrocyon, are also transferred to either Cynelos or Amphicyon. Results from this study, combined with previous work on the Moghra carnivores, suggests that at least three and perhaps as many as four very large carnivorous genera co-existed at Moghra: Cynelos, Amphicyon, Hyainailouros Stehlin, 1907 and possibly Megistotherium Savage, 1973. These giants represent the top predators of the Early Miocene of Africa, with Cynelos being more carnivorous, and Amphicyon, Hyainailouros and Megistotherium having more developed bone-crushing capabilities. RÉSUMÉ Nouveaux amphicyonidés (Mammalia, Carnivora) du Miocène inférieur de Moghra, Égypte. Nous décrivons ici deux mandibules de grands amphicyonidés (Amphicyonidae, Carnivora) de Moghra, Miocène inférieur, Égypte. L'une appartient à une nouvelle espèce de Cynelos Jourdan, 1862 de la même taille que C. macrodon (Savage, 1965) et C. ginsburgi n. comb., mais dont la lame du paraconide est relativement plus longue. L'autre est attribuée à Amphicyon giganteus (Schinz, 1825). À partir de ce nouveau matériel, les différences entre Cynelos, Amphicyon Lartet in Michelin, 1836 et Afrocyon Arambourg, 1961 sont clarifiées. De là nous déterminons trois (P4, M1, M2) sur quatre dents d'amphicyonidés isolées et non associées de Moghra, précédemment attribuées à « Cynelos sp. nov. » à Amphicyon giganteus. Cela représente la première signalisation de dents supérieures d'A. giganteus en Afrique. Les diagnoses remaniées de Cynelos et Amphicyon permettent également de ré-attribuer certains spécimens appartenant à ces taxons décrits précédemment. Cela permet d'attribuer « Amphicyon sp. » et une m2 isolée du Djebel Zel...

Caught in travertine: computed tomography reveals the youngest record of Amphicyon giganteus from the travertine deposits of Karacalar (late middle Miocene, central Anatolia, Turkey)

“…1–15 2018 Amphicyon giganteus Bastl, Nagel, Morlo and Göhlich ( 2018 ), p. 4, fig. 2 2019 Amphicyon giganteus Morlo, Miller, Bastl, Abdelgawad, Hamdan, El-Barkooky and Nagel ( 2019a ), p. 739, fig. 4 2020 Megamphicyon giganteus Siliceo, Morales, Antón and Salesa ( 2020 ), pp.…”

“…Both the premolars and the metaconid of m1 are clearly in reduction, which would suggest an adaptation to hypercarnivory similar to genera such as Tomocyon or Agnotherium (Morlo et al 2019a , b ; Viret 1929 ). Unlike Agnotherium , however, the metaconids on the m1 and the premolars are not as extremely reduced (Morlo et al 2019a , b ). Tomocyon also does not possess a metaconid on the m1.…”

“…Error bars represent the size ranges of the teeth. The data were taken from Ginsburg and Antunes ( 1968 ), Peigné ( 2012 ), Morlo et al ( 2019a , b ), Peigné et al ( 2006a , b ) …”

New suoid fossils (Mammalia, Artiodactyla) from the Miocene of Moghara, Egypt, and Gebel Zelten, Libya: biochronological implications

“…The 87 Sr/ 86 Sr analyses revealed that the Moghara sequence ranges in age from 21 Ma near the base of the section to around 17 Ma at its top. Most of the specimens from the CUWM collection were collected from the lower to middle part of the section, ranging in age from 19.6 to 18.2 Ma, however, a few specimens were collected from deposits approaching 17 Ma (Hassan 2013, Morlo et al 2019, Georgialis et al 2020.…”

Oldest co-occurrence ofVaranusandPythonfrom Africa—first record of squamates from the early Miocene of Moghra Formation, Western Desert, Egypt

“…Fossil vertebrates from Moghra are well known since the late 19th century (Jennings-Bramley, 1897;Andrews, 1899;Andrews, 1900;Blanckenhorn, 1901;Fourtau, 1918;Fourtau, 1920). The locality is nevertheless primarily known and mostly famous for its diverse mammal fauna (Rasmussen, Tilden & Simons, 1989;Miller & Simons, 1998;Miller, 1999;Sanders & Miller, 2002;Pickford, Miller & El-Barkooky, 2010;Miller et al, 2014;Morlo et al, 2019). Bird (Miller, Rasmussen & Simons, 1997;Smith, 2013) and fish (Cook et al, 2010;Abdel Gawad et al, 2016) remains are also known from Moghra.…”