A NEW SPECIES OF MOERITHERIUM (PROBOSCIDEA, MAMMALIA) FROM THE EOCENE OF ALGERIA: NEW PERSPECTIVES ON THE ANCESTRAL MORPHOTYPE OF THE GENUS

Abstract

A new species of Moeritherium (Proboscidea, Mammalia), M. chehbeurameuri sp. nov., is described from remains discovered in the early late Eocene locality of Bir El Ater, Algeria. Although mainly represented by isolated teeth, it shows distinct synapomorphies which justify its attribution to the genus Moeritherium, together with exclusive features that led to the creation of the new species. The main characteristic of this new taxon is the almost complete lophodonty shown by its molars, while Moeritherium is commonly regarded as a bunolophodont to bunodont taxon. In addition to this lophodonty, this new taxon shows anatomical features as yet unknown for the genus, but often met within lophodont early proboscidean taxa such as Phosphatherium escuilliei and Numidotherium koholense. Although a revision of the whole genus Moeritherium is outside the scope of this paper, the main controversies and discussion about the definition of species within the genus Moeritherium are discussed. The surprising lophodonty of M. chehbeurameuri, together with its small size, its early late Eocene age and the weak molarization of its P 3 support the hypothesis of a lophodont hypothetical ancestor for moeritheres, and therefore strengthen the growing hypothesis of a lophodont dental ancestral morphotype for proboscideans.

New rodent assemblages from the Eocene Dur At-Talah escarpment (Sahara of central Libya): systematic, biochronological, and palaeobiogeographical implications

“…algeriensis ), thereby suggesting a younger age for the Dur At‐Talah deposits. However, both localities share the recently described proboscidean Moeritherium chehbeurameuri Delmer et al. , 2006.…”

“…algeriensis), thereby suggesting a younger age for the Dur At-Talah deposits. However, both localities share the recently described proboscidean Moeritherium chehbeurameuri Delmer et al, 2006. Concerning the comparisons with the lowermost Fayum localities, the L41 rodent assemblage (Holroyd, 1994) contains more derived species than that of Dur At-Talah, and contains primitive species of the Oligocene Jebel El Qatrani rodent assemblages.…”

New fossils of Hyaenodonta (Mammalia) from the Eocene localities of Chambi (Tunisia) and Bir el Ater (Algeria), and the evolution of the earliest African hyaenodonts

“…The fossil locality of Bir el Ater, which is located in the Nementcha Mountains (North-eastern Algeria) ( Figure 1.1), is much younger than Chambi: its age is generally considered to be either latest Bartonian or earliest Priabonian (Figure 1.2). It has yielded a diverse assemblage of mammals including rodents (Coiffait et al, 1984;Jaeger et al, 1985;Marivaux et al, 2014a), primates (de Bonis et al, 1988Tabuce, 2002), an elephantshrew (Tabuce et al, 2001a), a hyracoid (Tabuce et al 2000), and a proboscidean (Delmer et al, 2006). Tabuce et al (2001b) listed the presence of creodonts gen. and sp.…”

New observations and reinterpretation on the enigmatic taxon Colombitherium (?Pyrotheria, Mammalia) from Colombia

“…Actually, the development or acquisition of bilophodonty presents much convergence in placental mammals, both intra‐ordinally (e.g. Barytherium / Numidotherium / Deinotherium within Proboscidea (Delmer et al. 2006); tapirs and paleotheres within Perissodactyla (Cuvier 1822)) and inter‐ordinally (xenungulates, perissodactyls, suid artiodactyls, pyrotherians, proboscideans, coryphodontid pantodonts, dinoceratans).…”