Victoria Quiralte

A new genus of tragulid ruminant from the early Miocene of Kenya

We re-describe the type material of the tiny African tragulid “Dorcatherium” moruorotensis from the early Miocene of Kenya, and erect the new genus Afrotragulus, the first African Miocene tragulid that does not belong to Dorcatherium. This new taxon is characterized by its elongated and stretched lower molars with a unique morphological dental pattern that strongly contrasts with that of Dorcatherium. We additionally include the former “Dorcatherium” parvum, also a small species from the early Miocene of Kenya, into the new genus Afrotragulus as Afrotragulus parvus, figuring it for the first time. We discuss the usefulness of body size as the main taxonomical criterion for studying the Tragulidae. And finally we comment on the taxonomical and morphological diversity of tragulids in the moment of their sudden early Miocene re-apparition and expansion in the Old World.

Dietary behaviour and competition for vegetal resources in two Early Miocene pecoran ruminants from Central Spain

ABSTRACT Dietary behaviour and competition for resources are investigated for the small-sized ruminants Andegameryx Ginsburg, 1971 and Procervulus Gaudry, 1877 representatives of two largely distinct states of diversification of pecorans. Results obtained from dental microwear and mesowear methodologies are concordant with a mixed feeder strategy for the taxa from the Early Miocene environments of the Iberian Chain (Central Spain). Further, the Spanish taxa investigated had less abrasive diets than their relatives from others similarly aged localities in Europe. This fact raises an important evolutionary uncertainty concerning the traditional characterization of first pecorans as specialized browsers. Instead, data strongly corroborate the recently proposed notion that some Pecora ruminant lineages were able to consume a mixture of browse and grass, and that were originally facultative mixed feeders. However, there is a large degree of variation of their dental wear features. Species were not dependent on a limited type of vegetation and, consequently, were able to exploit different food resources. Dental wear data seem to indicate that these ruminants did not compete for vegetation. In addition, last Andegameryx and earliest Procervulus apparently had a sufficiently different body size to partition the available vegetation in terms of height above ground level to elude competition. Body size difference coupled with an important degree of dietary opportunism may have been factors necessary for their coexistence.

The First Known Asian Hispanomeryx (Mammalia, Ruminantia, Moschidae)

The first known Asian Hispanomeryx (Mammalia, Ruminantia, Moschidae) Israel M. Sanchez a , Daniel Demiguel b , Victoria Quiralte a & Jorge Morales a a Departamento de Paleobiologia, Museo Nacional de Ciencias Naturales-CSIC, C/ Jose Gutierrez Abascal 2, 28006, Madrid, Spain b Institut Catala de Paleontologia, Universitat Autonoma de Barcelona, Edifici ICP, Campus de la UAB s/n, 08193, Cerdanyola del Valles, Barcelona, Spain

Systematics and evolution of the Miocene three-horned palaeomerycid ruminants (Mammalia, Cetartiodactyla)

Palaeomerycids were strange three-horned Eurasian Miocene ruminants known through fossils from Spain to China. We here study their systematics, offering the first cladistic phylogeny of the best-known species of the group, and also reassess their phylogenetic position among ruminants, which is currently disputed. The beautifully preserved remains of a new palaeomerycid from middle Miocene deposits of Spain, Xenokeryx amidalae gen. et sp. nov., helps us to better understand palaeomerycid anatomy, especially that of the nuchal region in the skull, significantly improving our current knowledge on these enigmatic ruminants. Our results show two main lineages of palaeomerycids, one containing the genus Ampelomeryx diagnosed by a characteristic type of cranium / cranial appendages and some dental derived traits, and another one that clusters those forms more closely related to Triceromeryx than to Ampelomeryx, characterized by a more derived dentition and a set of apomorphic cranial features. Xenokeryx branches as a basal offshoot of this clade. Also, we find that Eurasian palaeomerycids are not closely related to North American dromomerycids, thus rejecting the currently more accepted view of palaeomerycids as the Eurasian part of the dromomerycid lineage. Instead of this, palaeomerycids are nested with the African Miocene pecoran Propalaeoryx and with giraffoids. On the other hand, dromomerycids are closely related to cervids. We define a clade Giraffomorpha that includes palaeomerycids and giraffids, and propose an emended diagnosis of the Palaeomerycidae based on cranial and postcranial characters, including several features of the cranium not described so far. We also define the Palaeomerycidae as the least inclusive clade of pecorans containing Triceromeryx and Ampelomeryx. Finally, we reassess the taxonomy of several palaeomerycid taxa.

First African record of the Miocene Asian mouse-deer Siamotragulus (Mammalia, Ruminantia, Tragulidae): implications for the phylogeny and evolutionary history of the advanced selenodont tragulids

New remains of the small tragulid Dorcatherium songhorensis Whitworth, 1958 from the Early Miocene fossil site of Napak XXI (Uganda) include the first significant sample of postcranial bones from this species ever described. The limb bones of this tragulid are very similar to that described in the Miocene Asian long-legged tragulids of the genus Siamotragulus Thomas et al., 1990, a type previously unknown in the African Miocene. A cladistic analysis links D. songhorensis to a Siamotragulus clade as its basal offshoot, so we propose the name Siamotragulus songhorensis (Whitworth, 1958) for this species. Also, the Siamotragulus clade belongs to a monophyletic group that includes Afrotragulus Sánchez et al., 2010 and the extant Asian genera Moschiola and Tragulus. This inclusive clade is characterized by both a derived selenodont dentition and an advanced postcranial skeleton. Additionally Siamotragulus shows some cursorial refinements reflected in its postcranial skeleton including the pecoran-like metatarsals III–IV. Siamotragulus songhorensis shows that the genus Siamotragulus was not endemic to Asia as previously thought, and that a highly diverse guild of tragulids, including different members of the advanced selenodont clade, inhabited Africa as early as the Early Miocene (19–20 Ma).

Sexual Dimorphism of the Frontal Appendages of the Early Miocene African Pecoran Prolibytherium Arambourg, 1961 (Mammalia, Ruminantia)

ISRAEL M. SANCHEZ,* ! 2 VICTORIA QUIRALTE,2 JORGE MORALES,2 BEATRIZ AZANZA,3 and MARTIN PICKFORD4; department of Zoology, Museum of Zoology, Cambridge University, Downing Street, Cambridge, CB2 3EJ, United Kingdom, ims32@cam.ac.uk; israelms@mncn.csic.es; 2Departamento de Paleobiologia, Museo Nacional de Ciencias Naturales-CSIC, C/ Jose Gutierrez Abascal, 2, 28006 Madrid, Spain; 3Departamento de Ciencias de la Tierra (Paleontologia), Facultad de Ciencias, Universidad de Zaragoza, 50009, Zaragoza, Spain; Departement Histoire de la Terre, UMR 7202 (CR2P) du CNRS, case postale 38, 8, rue Buffon, 75005 Paris, France

Presencia del bóvido Austroportax en el yacimiento mioceno de Batallones-1 (MN 10, cuenca de Madrid, España)

Bovid fossils constitute rare findings in the Cerro de los Batallones fossil sites. However, maxillar and mandibular remains of a juvenile individual of a large-sized bovid were discovered in Batallones-1. In the present work, we describe these fossils and assign them to the Eurpoean genus Austroportax (Sickenberg, 1829). We name these fossils as Austroportax sp. due to the lack of more diagnostic additional material belonging to this form.