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Prolagus figaro and P. sardus are part of an endemic insular anagenetic lineage that populated Sardinia since the earliest Late Pliocene to Holocene. BM of some populations of these two species was calculated using regression models. The best BM proxies for Prolagus are: femur length, zeugopod measurements and distal humerus diameter. The anagenetic lineage show a BM increase of ca 20% from the populations of P. figaro (398−436 g) to P. sardus (504−525 g). The trend shown by the size of lower third premolar, even if not directly comparable with BM, is opposite (ca -30% at the transition P. figaro−P. sardus). Compared to P. cf. calpensis, a continental species of similar age, BM of P. figaro is ca +25%. The comparison with the insular endemic P. apricenicus evidenced differences in BM range and timespan required to attain it, due to the different size and palaeogeographical situation of the islands. Insular endemic Prolagus follow the small mammal pattern of Island Rule. Mein’s (1983) biphasic model seems applicable to the evolution of P. figaro. A tachytelic phase followed by a bradytelic one seems to characterize also the appearance of P. sardus, at least for dental traits, a process probably triggered by important variations of abiotic and biotic traits of the environment, as indicated by the turnover that marks the onset of the Dragonara subcomplex. The prediction of life history traits and other biological attributes of Sardinian Prolagus using BM should be considered with caution due to the complexity of ecological selective regimes of Sardinia.

Stasis, random walk and directional evolutionary patterns have been tested on the lower and upper first molars of the Rhagapodemus-Rhagamys lineage (Rodentia, Muridae) from Middle and Late Pleistocene fissure fillings of Monte Tuttavista, Orosei, Sardinia, Italy. We recorded the maximum length/maximum width ratio and size on 252 lower first molars and 208 upper first molars belonging to different fossil samples of Rhagapodemus minor and Rhagamys orthodon in order to explore evolutionary dynamics underlying molar morphology evolution. Akaike Information Criterion (AICc) was used for selection of the best model of evolution, in order to distinguish different evolutionary patterns. Our results clearly show that Rhagapodemus-Rhagamys lineage undergoes stasis during the middle and late Pleistocene of Sardinia, while size shows a random walk pattern between populations, characterized by an increase in size at the Rhagapodemus minor-Rhagamys orthodon transition.

This paper formally describes some cranial and postcranial remains of young and adult fossil suids retrieved from Monte Tuttavista karst fissures (Orosei, western Sardinia). The material is herein attributed to the Sardinian species Sus sondaari Van der Made, 1999. Features of skulls, mandibles, some milk teeth, definitive canines, and thus far unknown post-cranial elements of Monte Tuttavista suids significantly integrate our knowledge of the endemic species Sus sondaari. An emended diagnosis is here proposed, including some new diagnostic features such as lower canine with scrofic section, and oval shape of scapular glenoid fossa. Finally, the challenging evolutionary relationships of Sus sondaari are briefly discussed.

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

This paper presents the main results related to the analysis of fossils of the endemic Sardinian canid Cynotherium, discovered during the past years within the rich fossiliferous karst deposits in the Monte Tuttavista area (Eastern Sardinia, Nuoro). The analysis indicates that the remains from various fissure infillings differ in size and dental characters, which are suggestive of evolutionary phases under endemic conditions. The chronological sequencing of fissures obtained based on the evolutionary stage of the fossil canid is consistent with that emerging from the analysis of the whole mammal assemblages occurring in the same fissures. The possible evolutionary relationships of the Sardinian canid to the Plio-Pleistocene mainland species are also considered; a derivation from a population of late Canis arnensis (or Canis mosbachensis) population is supported.

The preliminary results of the analisys of fossil vertebrate remains from 19 fissure fillings in the karst network at Monte Tuttavista (Orosei, NMoro) are reported. about 80 taxa, among fishes, amphibians, reptiles, birds and mammals have been recognised.These remains document the evolution of vertebrate assemblages in the Sardinian insular domain, during a time interval apparently spanning the Late Pliocene to Late Pleistocene or Holocene. A succession of at least four populating complexes has been identified which document the vertebrate colonisation phases from the Italian mainland and the following periods of insularity. Indeed, the occurrence of endemic taxa such as the murid Rhagapodemus minor, the primate Macaca cf. M. majori and the caprine Nesogoral, suggest some fissure fillings date to a phase close to the Plio/Pleistocene boundary since these taxa occur at the Sardinian locality Capo Figari I which has been dated to about 1.8 Ma. However, the presence of the "hunting-hyaena" Chasmaporthetes, never reported before in Sardinia, could suggest that the beginning of the vertebrate record of Monte Tuttavista is older, given that this carnivore is documented in European Middle Pliocene-Early Pleistocene localities. The vertebrate assemblages that document the most recent migratory phases in the karst network of Monte Tuttavista are characterised by the occurrence of the endemic megalocerine cervid Praemegaceros cazioti and the arvicolid Tyrrhenicola henseli which are comparable with those occurring in other Late Pleistocene and early Holocene Sardinian sites.

Occurrence of large carnivores in island ecosystems is unusual, especially in the case of top predators. Here, a new endemic hyaenid species, Chasmaporthetes melei, from the late Late Pliocene to earliest Pleistocene fissure fillings of Monte Tuttavista, Orosei, Sardinia, is described. Although smaller, C. melei is morphologically comparable with the Plio-Pleistocene Eurasian hunting-hyena Chasmaporthetes lunensis, a possible ancestor of the Sardinian species. C. melei displays all the characteristic feeding adaptations of Chasmaporthetes, including a derived enamel structure similar to the condition in extant bone-crushing hyaenas. C. melei was an active predator that nonetheless included a relatively large amount of bone in its diet. SHORT NOTES