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Abstract: New or poorly known Soricids from the Early Miocene of Central France (Limagne d’Allier) and from the Middle Miocene of South-Eastern France (near Lyon) are studied; one new genus (Viretia) and a new species (Carposorex burkarti) are described. The soricid assemblages of the Early and late Early/Middle Miocene localities are totally different from each other and new information about appearance and evolution of the taxa are introduced. The following are lists of studied taxa for the beginning of the Early Miocene: Clapasorex bonisi, Clapasorex aff. sigei, Carposorex burkarti nov. sp., Soricella cf. discrepans, Oligosorex aff. antiquus and Crocidosoricinae indet, and for the late Early/Middle Miocene Dinosorex sansaniensis, Dinosorex pachygnathus, Heterosorex delphinensis, Miosorex desnoyersianus, Miosorex grivensis, Lartetium dehmi, Lartetium ziegleri, Turiasorex pierremeini, Viretia nov. gen. gracilidens, Paenelimnoecus micromorphus, Paenelimnoecus crouzeli and Hemisorex robustus.

Abstract: The late Oligocene birds of the Créchy quarry (Allier, France) with a description of two new genera (Aves: Pelecaniformes: Phalacrocoracidae, and Anseriformes: Anseranatidae). The Créchy quarry includes several fossiliferous layers, the fauna of which has been dated by micromammals to the latest Oligocene (reference-levels MP 29 and MP 30). Most of the birds belong to the same species as those which are widespread in the early Miocene localities (MN 2a) of the Saint-Gérand-le-Puy area. However, they differ from these Miocene avifaunas by the presence of a primitive form of Phalacrocoracidae,Borvocarbo guilloti n. gen. n. sp., and by a small representative of the Recent family Anseranatidae,Anserpica kiliani n. gen. n. sp. Most of these forms are aquatic birds which probably lived on lakes or on their shores.

According to F. M. Catzefliset al. (Trends Ecol. Evol.7, 122–126, 1992), comparative dating of the oldest dichotomy in the muroid group (Spalacinae-other Muridae) by molecular and paleontological time scales produces conflicting results. For the earliest Spalacinae they refer to a date of 25–37 Ma; however, it has been demonstrated thatRhizospalax is not a muroid rodent, and a review of the record of fossil Spalacinae suggests that paleontological and molecular dating produces a comparable age (±19 Ma).

As early as the Miocene basis, Steneofiber, an European Castorid genus, evidenced a reproductive strategy similar to that of the extant Castor: a two-years long breeding pattern. At the same time, in North America, a group of burrowing Castorids flourished and some of them dug helicoidal burrows (Daimonelix) with a basal living chamber in which the youngs were raised. The fossorial branch of Castorids disappeared at the end of the Lower Miocene but the aquatic one continued until now with periodic radiations that seem to be related to palaeogeographic changes. In the other families of Oligocene rodents, the hypothesis concerning the relationship between the value of the D4/P4 length ratio and the life-history strategies is discussed; our current knowledge seems to be too fragmentary to draw valuable conclusions.

Three glirids are described in the Oligocene mammal local fauna of Paguera (Majorca, Spain); one of them, Bransatoglis adroveri nov. sp. exhibits a mixture of primitive and derived characteristics; the latter developed only in the Lower Miocene representatives of this lineage. In the Paguera fauna, the abundance of glirid teeth showing numerous crests clearly indicates forested areas. The particularities of two of the three glirids of Paguera could be due to a certain degree of isolation and attest the changing relationships of Majorca with continental areas (Eurasia, Africa).

The new species Theridomys octogesensis is described from two Upper Oligocene localities of the Ebrobasin: from the Eastern margin, in Mina del Pilar 3 (late Oligocene, MP 27) and from the older levels of Alcorisa (MP 26a), on the Southern border. Theridomys octogesensis is the largest and the most hypsodont species of the Theridomys group, as well as the last member of the genus. It extends the stratigraphical range of the genus and raises the question of a parallel but particular evolution of a Spanish Theridomys branch.

The fresh-water limestone deposits of Montaigu-le-Blin yielded a small pocket containing almost exclusively cranial and post-cranial elements of the castorid Steneofiber. A full inventory of these skeletal remains makes it possible to recognize an assemblage of two adults and eight juveniles of two different ages. It corresponds well to a family group of the extant beaver, usually consisting of an adult breeding pair together with a variable number of yearlings and kits; consequently this pocket is interpreted as a fossil burrow containing the catastrophic death-assemblage of a Steneofiberfamily, and we infer a K-strategy model of reproductive pattern for this genus. Moreover, a minute fossil ungual phalanx corresponds well to the “combing-claw” of the extant beaver and suggests the development of nonwettable fur, an important adaptation to a semiaquatic way of life. The shape of the fossil caudal vertebrae, without the wing-like transverse processes of Castor, indicates that the tail of Steneofiberwas cylindrical, however.

As early as the Miocene basis, Steneofiber, an European Castorid genus, evidenced a reproductive strategy similar to that of the extant Castor: a two-years long breeding pattern. At the same time, in North America, a group of burrowing Castorids flourished and some of them dug helicoidal burrows (Daimonelix) with a basal living chamber in which the youngs were raised. The fossorial branch of Castorids disappeared at the end of the Lower Miocene but the aquatic one continued until now with periodic radiations that seem to be related to palaeogeographic changes. In the other families of Oligocene rodents, the hypothesis concerning the relationship between the value of the D4/P4 length ratio and the life-history strategies is discussed; our current knowledge seems to be too fragmentary to draw valuable conclusions.