An extraordinary gobioid fish fossil from Southern France.

BackgroundThe classification of gobioid fishes is still under discussion. Several lineages, including the Eleotridae and Butidae, remain difficult to characterize because synapomorphies are rare (Eleotridae) or have not yet been determined (Butidae). Moreover, the fossil record of these groups is scarce.ResultsExceptionally well-preserved fish fossils with otoliths in situ from uppermost Oligocene sediments (≈23-24 Mio. y. ago) in Southern France provide the most in-depth description of a fossil gobioid to date. The species was initially described as Cottus aries Agassiz, then transferred to †Lepidocottus Sauvage, and subsequently assigned to Gobius. Based on a comparative analysis of meristic, osteological and otolith data, this species most likely is a member of the family Butidae. This discovery is important because it represents the first record of a fossil butid fish based on articulated skeletons from Europe.SignificanceThe Butidae and Eleotridae are currently distributed in W-Africa, Madagascar, Asia and Australia, but they do not appear in Europe and also not in the Mediterranean Sea. The new results indicate that several species of the Butidae thrived in Europe during the Oligocene and Early Miocene. Similar to the recent Butidae and Eleotridae, these fishes were adapted to a wide range of salinities and thrived in freshwater, brackish and marginal marine habitats. The fossil Butidae disappeared from Europe and the Mediterranean and Paratethys areas during the Early Miocene, due probably to their lack of competitiveness compared to other Gobioidei that radiated during this period of time. In addition, this study documents the great value of otoliths for gobioid systematics

Reassessing the earliest oligocene vertebrate assemblage of monteviale (vicenza, italy)

The faunal assemblage of Monteviale (Vicenza, northern Italy) represents a rare condition among the earliest Oligocene assemblages of south-eastern Europe at the ‘Grande-Coupure’. The lignitic fossiliferous strata lie above explosive basaltic breccias produced by a volcanic complex raised within a lagoon where the Calcareniti di Castelgomberto Formation (earliest Oligocene in age) was deposited. Systematic revision of the vertebrate remains from Monteviale reveals the presence of 15 taxa belonging to ?Butidae, Palaeobatrachidae, Trionychidae, Geoemydidae, Diplocynodontinae, Dugongidae, ?Pantolesta, Chiroptera, Rhinocerotidae, Anthracotheriidae and Palaeochoeridae. The fossiliferous deposit of Monteviale probably originated in a coastal lagoon characterized by salinity fluctuations, from brackish to fresh water, the latter evidenced by the presence of palaeobatrachid larvae. The terrestrial vertebrate assemblage indicates a humid forest environment with an age close to the EoceneOligocene boundary, lowermost Rupelian, MP21. Some of the mammal taxa (e.g. Epiaceratherium, Anthracotherium and ?Propalaeocherus) of Monteviale show a clear affinity with older (late Eocene) southern Asian species, suggesting a dispersal pattern across the several plates of south-eastern Europe and western Asia. By contrast, the herpetofauna (e.g. Trionyx, Bergouniouxchelys and Diplocynodon) suggests a closer relationship to European taxa