Chiara Angelone

The small mammals from Gratkorn: an overview

The rich and diverse fossil mammalian assemblage from Gratkorn (Middle Miocene, Austria) is of primary importance for the understanding of the faunal evolution in Central Europe. Besides large mammals, the fauna comprises: Schizogalerix voesendorfensis, Galericinae gen. et sp. indet., Desmanodon fluegeli, Dinosorex sp., cf. Myotis sp., “Cricetodon” fandli, Megacricetodon minutus, Eumyarion sp., Spermophilinus bredai, Blackia sp., Forsythia gaudryi, Albanensia albanensis, Muscardinus aff. sansaniensis, Miodyromys sp., Keramidomys sp., Euroxenomys minutus minutus, Prolagus oeningensis, cf. Eurolagus fontannesi and Ochotonidae indet. Based on the degree of corrosion on the dental elements and the presence of pellets, most, but not all, of the material is tentatively interpreted as a result of accumulation by nocturnal raptors. In addition to the information provided by the lower vertebrates and the molluscs, which occur in abundance in the same thin fossil-enriched layer, the mammal fauna gives a mixed picture of the environment (basically forested vs. open landscape). This could indicate the presence of different microhabitats around the excavation place, but may also be a taphonomical artefact based on various different agents of accumulation contributing to the thanatocoenosis. Nevertheless, the extreme quick accumulation of the fossils provides an exceptional windows in the late Sarmatian s. str. ecosystems.

Complement to the study of the pikas (Lagomorpha, Ochotonidae) from the Middle Miocene of Gratkorn, Austria

An update about the Middle Miocene ochotonids (Lagomorpha, Mammalia) from Gratkorn, Austria, is presented. The presence of Prolagus oeningensis (König, 1825), previously attested based on the description of two well-preserved lower mandibles is confirmed, and complementary material is added. In addition, isolated teeth of a rooted ochtonid allow the recognition of the presence of cf. Eurolagus fontannesi (Depéret, 1887). A third ochotonid (Ochotonidae indet.), characterised by large-sized and ever-growing teeth, is another new element of the Gratkorn assemblage, although it cannot be taxonomically assigned, even at the genus level, because of the lack of diagnostic material. The fossil community is discussed in the central and eastern European context during Sarmatian times.

Two new species of Prolagus (Lagomorpha, Mammalia) from the Late Miocene of Hungary: taxonomy, biochronology, and palaeobiogeography

The present study describes two new species, Prolagus pannonicus sp. nov. and P. latiuncinatus sp. nov., from the Late Miocene Hungarian localities Sümeg (MN10/11) and Polgárdi 2 (MN13). These species are closely related, probably by a direct ancestor–descendant relationship. They share characters common to Late Miocene–Pliocene eastern European species (e.g., the retention of the entoconid enamel in p3 contrarily to coeval western European ones), attesting to an eastern European group of Prolagus that evolved independently from western European species at least since MN10/11. Nevertheless, the two Hungarian species of Prolagus here described follow particular evolutionary trends: contrarily to other European Late Miocene species, their p3 does not undergo a substantial size increase after MN12, whereas the crochet size enlarges noticeably. Special emphasis is given to the comparison of P. pannonicus sp. nov. and P. latiuncinatus sp. nov. with the Gargano insular endemic Prolagus species. Their common morphological traits are related to convergence due to endemism. Prolagus pannonicus sp. nov. and P. latiuncinatus sp. nov. probably were continental isolated species.KurzfassungDie vorliegende Studie beschreibt zwei neue Arten: Prolagus pannonicus sp. nov. und P. latiuncinatus sp. nov. aus den spätmiozänen ungarischen Lokalitäten Sümeg (MN10/11) und Polgárdi 2 (MN13). Diese Arten sind eng verwandt, wahrscheinlich über eine direkte Vorfahren-Nachkommen-Beziehung. Sie teilen Merkmale, die spätmiozän-pliozänen osteuropäischen Arten gemein sind (z. B. den Erhalt des Entoconid-Schmelzes an p3 im Gegensatz zu zeitgenössischen westeuropäischen Arten), und bezeugen so eine osteuropäische Abstammungslinie, die bereits seit MN10/11 von den westeuropäischen getrennt verläuft. Allerdings folgen die beiden hier beschriebenen ungarischen Arten des Prolagus besonderen Evolutionstrends: Im Gegensatz zu anderen spätmiozänen europäischen Arten vergrößert sich ihr p3 nach MN12 nicht substantiell; es zeigt sich hingegen eine bemerkenswerte Vergrößerung des Crochet. Besonderes Gewicht wird auf den Vergleich von P. pannonicus sp. nov. und P. latiuncinatus sp. nov. mit dem insular-endemischen Prolagus aus dem Gargano gelegt. Ihre gemeinsamen morphologischen Merkmale hängen mit Konvergenz aufgrund von Endemismus zusammen. Wahrscheinlich waren Prolagus pannonicus sp. nov. und P. latiuncinatus sp. nov. kontinental isolierte Arten.

Systematics and paleobiogeography of Sardolagus obscurus n. gen. n. sp. (Leporidae, Lagomorpha) from the early Pleistocene of Sardinia

Abstract. The extreme rareness of Sardinian fossil sites older than Middle and Late Pleistocene makes the Monte Tuttavista karst complex (E Sardinia, Italy) very important. Remarkable lagomorph material, recovered from several fissure infillings of Monte Tuttavista referable to the Capo Figari/Orosei 1 and Orosei 2 faunal sub-complexes (early Pleistocene, ∼2.1/1.9–1.1 Ma), allowed us to describe a new endemic insular leporid, Sardolagus obscurus n. gen. n. sp. The new taxon is characterized by a peculiar combination of an advanced p3 (Lepus-type) and a primitive P2 lacking deep flexa. The origin of such discrepancy, unprecedented among continental and insular endemic European leporids, is unclear. It could be the result of: (1) an independent evolution of p3 from an ancestor bearing the primitive P2/p3 (e.g., Alilepus, Hypolagus), or (2) a selective reversal morphocline from an Oryctolagus/Lepus-like leporine. The lack of data about the phylogenetic origin of the new taxon makes any inference about its possible arrival to Sardinia problematic. Crossing the European leporid records and evidence of migrations to Sardinia, we hypothesize three possible ages in which the ancestor of Sardolagus obscurus could have arrived in Sardinia, restricted to the late Miocene-early/late Pliocene (∼8–3.6 Ma). The phylogenetic relationship between Sardolagus obscurus n. gen. n. sp. and the oldest Sardinian leporid, recorded from Capo Mannu D1 and dated at the early/late Pliocene boundary (∼3.6 Ma), is unclear at present, however it is quite likely that they pertain to the same lineage.

Determining the ontogenetic variation of lower cheek teeth occlusal surface patterns in lagomorphs using micro-ct technology

Micro CT-scanning has been performed on the lower jaws of some selected lagomorph taxa in order to reconstruct unequivocally their controversial ontogenetic development. The analyses were concentrated on the development of p3, and on the sequences of lobe connections and on the sequence of appearance/disappearance of flexids/fossettes of p4-m2. This is the first time that this approach has been applied to lagomorphs and opens promising perspectives especially for the taxonomy and phylogeny of this complex order. Chiara Angelone. Institut Catala de Paleontologia, Universitat Autonoma de Barcelona, 08193 Cerdanyola del Valles, Barcelona, Spain, chiara.angelone@icp.cat Julia A. Schultz. Steinmann-Institut fur Geologie, Mineralogie und Palaontologie, Universitat Bonn, Nussallee 3, 53115 Bonn, Germany, schultzj@uni-bonn.de Margarita A. Erbajeva. Geological Institute, Siberian Branch, Russian Academy of Sciences, Ulan-Ude, Russia 670047, erbajeva@gin.bscnet.ru