The Abruzzo-Apulian (Central and Southeastern Italy) fossil fauna, new challenges for paleontologists and paleobiogeographers

The Abruzzo-Apulian Platform was an endemic Neogene paleobioprovince. Its relics can be found at the south-east of the Italian Peninsula. Geological and paleontological traces of this past land crop out both in the central Apennines, Maiella (Scontrone fossiliferous site), as well as in the Gargano Promontory. The Scontrone paleofauna -Scontrone is placed on the southern borderline of the Abruzzo National Park, Central-Southern Apennine. The bone-bearing sediments are coastaltidal-flat calcarenites stratigraphically dated to the Lower Tortonian. They yielded remains of terrestrial mammals, which include the bizarre ruminant Hoplitomeryx and the giant insectivore Deinogalerix, of a large terrestrial bird, and of large crocodilians and chelonians. At present, Hoplitomeryx, Deinogalerix and the crocodilians represent the elements in common with the Gargano community. The fauna is endemic and quite unbalanced. Six species of Hoplitomeryx have been described until now, but other species are adding to the list as new specimens are being freed from the calcarenites. Deinogalerix seems also represented by more than a single species. No mammal carnivores nor small mammals were found until now. The Gargano paleofauna - A very diversified endemic fauna is contained in soil deposits (Terre Rosse) that fill an extensive karst system at the north-western slopes of Mount Gargano (Southern Italy). The fossil assemblages include both large and small mammals, birds, reptiles, and amphibians, and are highly unbalanced. The small mammal component is mainly made of rodents, lagomorphs, and insectivores. Larger mammalian taxa are less abundant and are represented by Hoplitomericidae, Deinogalerix. And the sea otter Paralutra garganensis. The fissure fillings have been arranged in a biochronological sequence based on their different faunal composition and evolutionary degree. During the time period documented by the fissure deposits the faunal diversity changed and several taxa underwent significant evolutionary modifications, giving rise to numerous adaptive radiations. Taxa weakly- or non-modified compared to their continental counterparts characterize the oldest assemblages. They likely represent the youngest dispersal phase from the mainland into the insular domain, suggesting a polyphasic origin of the community.Evidence of apparently the oldest faunal settlement in Gargano was found in the recently discovered fissure M013. It contains remains of a new murid, which is manifestly the ancestor of Mikrotia (the endemic and widespread murid of the Terre Rosse), together with those of a new Cricetodontinae, which resembles primitive early Miocene representatives. These occurrences, in addition to the absence of Apodemus and Prolagus, two ubiquitous taxa of the Terre Rosse fillings, confirm that the assemblages are the result of a set of successive bioevents. The age and paleogeography of Scontrone and Gargano: the Abruzzo-Apulian domain - The Early Tortonian age of the Scontrone fauna is unequivocally proven not only by solid geologic evidence, but also by the Hoplitomeryx representatives, which are comparatively more primitive than their Gargano counterparts. The same might apply to the Deinogalerix specimens from the two localities, but analyses are still under way to check this aspect. The Gargano fissure fillings are tentatively dated to the Late Miocene on the basis of paleontological inferences, namely the occurrence of Apodemus, which is supposed to be not older than MN12 in the European mainland. The Gargano’s younger age possibly reflects the fact that the Gargano palaeo-islands formed stable structural high, while the Scontrone area was involved in the Apennine build-up and gradually sunk. Thus, the faunas from Scontrone and Gargano represent two different time slices within the same bioprovince. The colonization of the Abruzzo-Apulia domain - The existence, from the Late Oligocene to the Langhian, of a trans-Adriatic structural high between Dalmatia and the Gargano Peninsula, through the present day Tremiti Islands, was ascertained based on the seismostratigraphic analysis of more than 6000 kilometers of reflection seismic profiles from the Adriatic offshore, but also on several tens of deep wells. The major 29-30 Ma global sea-level fall caused the generalized surfacing of this structure across the Adriatic. The trans-Adriatic isthmus was originally in the form of stripe of land. Then, as the sea level turned growing at the transition to the Early Miocene, the structural high likely gave rise to an archipelago of gradually shrinking islands. The isthmus definitively sank at the end of the Langhian, i.e. around 14.8 Ma, and the Abruzzo-Apulian area remained cut off from any near mainland for the next 7 million years. Dalmatia and the Gargano were connected again during the Messinian sea lowstand. Thereafter, the sea level turned gradually to rise again, at first isolating the Abruzzo-Apulian area and then finally submerging it entirely at the very end of the Messinian. The possible ways of colonization used by the Messinian colonizers is still passionately debated. Although many steps have been made in the direction of improving our understanding of the history of the Abruzzo-Apulian Platform and of its faunal communities, yet many issues are still unanswered. Settling these issues will not only give us a better insight into the development of the Abruzzo-Apulian faunas per se, but will also lead us to a better understanding of the geo– and biodynamics of paleoislands in general

New insular taxa from the oldest Terre Rosse fissure filling (Gargano, Southeastern Italy).

A rich amount of fossil remains of a highly diversified vertebrate fauna, known as “Mikrotia fauna”, has been retrieved from the red soil deposits (Terre Rosse) which fill the extensive palaeokarst network that affects the Mesozoic limestone along the north-western slopes of Mount Gargano (Southern Italy). The faunal assemblages reveal a rather complex history of bioevents such as dispersals and extinctions, which occurred when the area was isolated. These reconstructions were based on the materials collected during the seventies and the eighties of the last century. Forty years after its discovery, the Gargano Terre Rosse finally yielded evidence of an older faunal settlement. The peculiar assemblage of the M013 fissure allows to explain some of the controversial aspects of the Gargano faunal history, namely, the matter of the biochronology of the older fissure fillings and the issue of the arrivals of the taxa in the insular domain. The taxonomic study of the small mammal assemblage from fissure M013, sampled by a team of the University of Torino during the 2005-09 excavations in the Dell’Erba Quarry (Apricena, Foggia), is here presented. Insectivores include a small-sized endemic Galericinae Apulogalerix cf. pusillus, together with a Crocidosoricinae, Lartetium cf. dehmi. Gliridae are well represented by the endemic species Stertomys simplex and S.lyrifer. Cricetids (l.s.) are represented by a single remain belonging to the endemic Hattomys cf. nazarii, but also by a new genus and species of an endemic and rather primitive Cricetodontinae. The latter shows a very hypsodont dental crown, stocky cusps and tubercle-like crests. Some of its features are typical of the continental genera of Cricetodontinae (i.e. large size, thick and crenulated enamel), however the very large size and the very high hypsodonty indicate the endemic nature of this taxon. The occlusal pattern appears rather primitive due to the very low, poorly developed, interrupted ectolophs and share some features with the primitive species of the genus Cricetodon. Murids include Mikrotia parva together with a second larger species, which is not yet identified. A third Murinae rodent is quite abundant, and belongs to a new genus and species. Its dentition is more brachyodont than in Mikrotia parva, the upper teeth are stephanodont and, accordingly, the transversal crests are joined by a longitudinal crest in the lower molars. Tubercle t7 is absent in the upper molars, t2bis is always present, while t1bis is usually absent in the first upper molar. Tubercle t1 is placed in a distal position respect to the t3, the posterolabial tubercle t12 is well-developed. Tubercles t3, t6 and t9 are roughly equidistant forming a regular pattern: a character that is found in Mikrotia and not in the other murid species, in which t6 is closer to t9. This morphological characters reveal a close relationship with Mikrotia, but they do not occur jointly in any of the Late Miocene-Earliest Pliocene European genera of murids, thus the phylogenetic origin of this new genus is still unclear. The occurrence of this new Murinae and of a Cricetodontinae distinguishes M013 from all the other Terre Rosse fissure fillings of Gargano. Stertomys lyrifer and S. simplex were previously known only from the very ancient fissure Rinascita 1. Because both taxa characterize M013 and Rinascita 1, the two fissures are believed to be very close chronologically. Also the Crocidosoricinae characterises the older fissure fillings. In contrast, M013 is the only fissure lacking Apodemus and Prolagus, which are otherwise present in all the other Gargano infillings. The accumulated evidence indicates M013 as the oldest of Gargano’s faunal assemblages, despite the occurrence of Hattomys cf. nazarii, Mikrotia cf. parva and Mikrotia sp1, which most probably results from infiltrations from younger fissure fillings. The M013 assemblage is an absolute novelty for the Abruzzo-Apulian Palaeobioprovince and opens a new perspectives for the timing and mode of dispersal of the forerunners of the Gargano fauna

NEW LIGHT ON PARASOREX DEPERETI (ERINACEOMORPHA: ERINACEIDAE: GALERICINI) FROM THE LATE MESSINIAN (MN 13) OF THE MONTICINO QUARRY (BRISIGHELLA, FAENZA, ITALY)

A large-sized species of Parasorex is common in the MN 13 mammal assemblages from the uppermost Messinian sandy-marly fissure fillings within the Gessoso Solfifera Formation at Brisighella (Northern Apennine). This erinaceid has been classified as Galerix sp. in the first papers on the Brisighella fauna. Later, it was described in detail in an unpublished Ph.D. dissertation by Fanfani (1999), who referred it to Galerix depereti. Van den Hoek Ostende (2001) included G. depereti in the genus Parasorex, Parasorex depereti has been described by Crochet (1986) on scarce material from a few Early Pliocene (MN 14–15) localities of southern France and Spain. Parasorex cf. depereti has been reported from the Early Pliocene fauna of Capo Mannu (Mandriola, Sardinia; Furió and Angelone 2010). The species seems actually distributed in south-western Europe, where it represents the youngest occurrence of the genus Parasorex. The very abundant sample of P. depereti from fissure filling BRS 25 enables a more accurate and comprehensive description of the species. It also permits inspection of the mesial elements of the dentition, which were lacking in the material examined by Crochet (1986). The systematic position of the species has been revisited and compared with those of other Galericini of the Parasorex group

A new small mammal assemblage from the Pirro 12 “Terre Rosse” fissure filling (Gargano, Southeastern Italy).

The Pirro 12 fissure filling has been discovered and sampled by a team of the University of Torino during the 2005 field survey in the Dell’Erba Quarry (Apricena, Foggia). The occurrence of a very small Deinogalerix and of a very simple Mikrotia supported, at a first glance, the very old position of Pirro 12 in the biochronological succession of endemic faunal settlements of Gargano (Villier, 2011). In this communication the preliminary result of taxonomic studies of the small mammal assemblage of the Pirro 12 filling is presented. The Gliridae is by far the most common family in this site. Two species of the endemic genus Stertomys have been identified: the small-sized Stertomys cf simplex, and the larger-sized Stertomys cf lyrifer. The possible occurrence of Stertomy daamsi still needs to be ascertained. These Myomiminae closely resemble those of fissure Rinascita 1 reported in the literature. Murids are represented by two species of Mikrotia: one is very small, with very brachyodont crown and simple morphology of M/1, while the other is somewhat larger and hyspsodont, and has a slightly more complex occlusal pattern. Another Murinae species is rather common and although it is still being analyzed, it is the first new taxon reported from Pirro 12. A second one is a very large-sized and rather hypsodont cricetid (latu sensu) genus, which cannot be associated with any other cricetid so far reported from the Gargano Terre Rosse. Insectivores are represented by three mandibles without teeth of a small-sized Galericinae, as well as by a single remain of Crocidurinae. The sample is rather poor, and therefore the absence of characterizing taxa should be considered with caution. The occurrence of a new murine and of a new large cricetid distinguishes the Pirro 12 assemblages from all other fissure fillings. The shrew is present also in some old fissure fillings reported in the literature of the 1980’s (Martín-Suárez & Freudenthal, 2007). Stertomys lyrifer and S. symplex are found only in the fissure Rinascita 1, which is the second oldest fissure mentioned in the literature of the late 1970’s (De Giuli et al., 1987). The absence of Apodemus and Prolagus, two genera which are virtually present in all known fissure fillings from the Gargano, the absence of Hattomys, the endemic resident cricetidae, the absence of Apocricetus, Neocricetodon and Democriceton which are instead found in older fissures (i.e., Rinascita 1 and Biancone), together with the extreme primitiveness of Microtia, prove the ancient biochronological age of this fissure, changing the scenario of the oldest faunal settlements of the Abruzzo- Apulian paleo-bioprovince

new light on parasorex depereti erinaceomorpha erinaceidae galericini from the late messinian mn 13 of the monticino quarry brisighella faenza italy

Abstract A large-sized species of Parasorex is common in the MN 13 mammal assemblages from the uppermost Messinian sandy-marly fissure fillings within the Gessoso Solfifera Formation at Brisighella (Northern Apennine). This erinaceid has been classified as Galerix sp. in the first papers on the Brisighella fauna. Later, it was described in detail in an unpublished Ph.D. dissertation by Fanfani (1999), who referred it to Galerix depereti. Van den Hoek Ostende (2001) included G. depereti in the genus Parasorex, Parasorex depereti has been described by Crochet (1986) on scarce material from a few Early Pliocene (MN 14–15) localities of southern France and Spain. Parasorex cf. depereti has been reported from the Early Pliocene fauna of Capo Mannu (Mandriola, Sardinia; Furió and Angelone 2010). The species seems actually distributed in south-western Europe, where it represents the youngest occurrence of the genus Parasorex. The very abundant sample of P. depereti from fissure filling BRS 25 enables a more accurate and comprehensive description of the species. It also permits inspection of the mesial elements of the dentition, which were lacking in the material examined by Crochet (1986). The systematic position of the species has been revisited and compared with those of other Galericini of the Parasorex group