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The Sardinian dhole (Cynotherium sardous)1 was an iconic and unique canid species that was endemic to Sardinia and Corsica until it became extinct at the end of the Late Pleistocene.2–5 Given its peculiar dental morphology, small body size, and high level of endemism, several extant canids have been proposed as possible relatives of the Sardinian dhole, including the Asian dhole and African hunting dog ancestor.3,6–9 Morphometric analyses3,6,8–12 have failed to clarify the evolutionary relationship with other canids.We sequenced the genome of a ca-21,100-year-old Sardinian dhole in order to understand its genomic history and clarify its phylogenetic position. We found that it represents a separate taxon from all other living canids from Eurasia, Africa, and North America, and that the Sardinian dhole lineage diverged from the Asian dhole ca 885 ka. We additionally detected historical gene flow between the Sardinian and Asian dhole lineages, which ended approximately 500-300 ka, when the land bridge between Sardinia and mainland Italy was already broken, severing their population connectivity. Our sample showed low genome-wide diversity compared to other extant canids—probably a result of the long-term isolation—that could have contributed to the subsequent extinction of the Sardinian dhole.

Financiado para publicación en acceso aberto: Universidade da Coruña/CISUG [Abstract] Body size is a useful character to unravel the biology of fossil taxa and, indirectly, the palaeoenvironment in which they lived. However, the reliability of size proxies is debated, particularly among insular endemics in which large teeth relative to body size have been observed. To shed light on this issue, here we compute statistical models to assess: (i) teeth and long bone scaling and (ii) dentition size evolutionary dynamics in the anagenetic lineage Prolagus figaro-P. sardus from the late Early Pleistocene-Holocene of Sardinia, Italy. Postcranial bones, particularly tibial epiphyses, are shown to be the most suitable parameters for prediction of body mass in Prolagus and other lagomorph taxa. By contrast, p3 should not be used for size reconstructions, whereas m1 width provided the highest correlation with long bones. On the other hand, the postcanine occlusal surface of Sardinian Prolagus (m1 and toothrow area) appeared significantly larger than those of extant lagomorphs, pointing to a higher resistance to tooth wear and a more durable permanent dentition. It seems likely that megalodontia might have evolved in Sardinian Prolagus to cope with the abrasive diet found on islands (food habit hypothesis). Nonetheless, we cannot exclude that other biological features, such as long longevity, could be co-driving forces in this fossil lineage (life history hypothesis). The results achieved throw light on size and scale evolution in lagomorphs, as well as refine the eco-evolutionary responses of small mammals to insular regimes. This work was supported by Consellería de Cultura, Educación e Universidade, Xunta de Galicia, Spain (BM-S, ED481B 2018/046, Axudas á etapa postdoutoral da Xunta de Galicia 2018 – Modalidade A), Visiting Professor grant of the President's International Fellowship Initiative of the Chinese Academy of Science (CA), Spanish Agencia Estatal de Investigación and the European Regional Development Fund of the European Union (CA, CGL2016-76431-P), CERCA Program of the Generalitat de Catalunya (CA), and Grant to Department of Science, Roma Tre University (CA, MIUR-Italy Dipartimenti di Eccellenza, ART. 1, C. 314-337L. 232/2016). Funding for open access charge: Universidade da Coruña/CISUG. Xunta de Galicia; ED481B 2018/046

The insular environment of Sardinia is renowned for its extensive palaeontological Palaeogene record, extending from the Eocene until recent times. In Sardinia, one of the most important localities for Quaternary faunas is the fillings of the karst fissures of the Monte Tuttavista site complex, which contain an impressive amount of fossil remains of around 70 vertebrate taxa. Several studies that have examined the network of the karst fissure cavities and their fossils have revealed some issues regarding the biochronological ordering, as well as some peculiarities in the recovered faunal associations (such as the presence of several carnivores). In this study, we analysed the record of the two large mustelids from this site, the genera Pannonictis and Enhydrictis. Our analyses point out several singular morphological and morphometric features of these taxa that suggest their attribution to two new species, Pannonictis baroniensis nov. sp. and Enhydrictis praegalictoides nov. sp. The proportions and the robust morphologies of P. baroniensis resemble those of other European taxa, such as P. pliocaenica, although other dentognatic and cranial features exclude a conspecific identity with previously known taxa. Conversely, E. praegalictoides represents the earliest member of the genus and shows a mixed pattern of derived features that are shared with the peculiar E. galictoides recovered from other Middle-Late Pleistocene Sardinian localities, as well as other more primitive characteristics that do not occur in this endemic mustelid. Considering the controversial debate regarding the evolutionary history of the tribe Galictini, the record of these new endemic species expands our knowledge of the systematics and the biogeography of the galictines and enriches the diversity of the tribe during the Early and Middle Pleistocene.

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.UUID: http://zoobank.org/ca8e0023-7c9d-4b00-a294-d166c37c5c71

This work describes a new bovid, Asoletragus gentryi n. gen. et sp., from the late Pliocene/early Pleistocene fossiliferous fissure fillings (Cava VI,3) in the karst network at Monte Tuttavista (Sardinia, Italy). It differs from other genera in its straight, almost conical, horn-cores, which diverge slightly from the sagittal plane, are very close together at their bases and slant strongly backwards (nearly parallel to the glenoid surface of the temporal bone). The very peculiar shape and position of these horn-cores render their phylogenetic relationship with other taxa from the Miocene of Europe and other circum-Mediterranean countries uncertain. Given the global features of the horn-cores and the absence of any alcelaphine-like tooth in the Monte Tuttavista samples, the hypothesis that Asoletragus belongs to an archaic "Caprinae" cannot be ruled out, despite the presence of quite a large frontal sinus rising through the pedicel and at least one-third of the horn-core proper. Pending the discovery of other fossils from this taxon, one may only hypothesize regarding its phylogeny. SHORT NOTE, Rivista italiana di Paleontologia e Stratigrafia, Vol 112, No 3