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We present estimates for head and body length (HBL) of fossil rodents. We assembled HBL data and tooth row length data (LTR, UTR) for a large number of extant rodents, and calculated regression lines of HBL on LTR and UTR for all rodents together (all-rodents equation), and for separate taxonomic groups (family equations). In fossil rodents, data for complete tooth rows are scarce, therefore we use the sum of the lengths of the teeth (LRsum, URsum) as a surrogate for tooth row length. The relation between this parameter and real tooth row length (LTR, UTR) is calculated on the basis of a number of populations for which both parameters are available. We estimate HBL of fossil rodents, using LRsum and URsum and the regression lines of extant rodents, and we compare the results for lower and upper tooth row when both are available. For each species we calculate HBL through the all-rodents equation and through the family equation. We consider the amount of difference between these two values as a measure of the reliability of this method. [ABSTRACT FROM AUTHOR]

The peculiar red colour of fossil small mammal remains from a late Miocene section in southern Spain suggests an unusual diagenetic alteration. These remains have been studied by means of environmental scanning electron microscope equipped with different detectors, energy dispersive X-ray spectroscopy and an inductively coupled plasma optical emission spectrometer. The red colour is caused by the presence of cinnabar ( Hg S) in the pores of the fossil bones and teeth, filling the dentinal and bone tubules and other cavities that at life were filled by organic matter. A nearby cinnabar outcrop in the metamorphic materials of Sierra Nevada is interpreted as the source of mercury. This element was mobilized by meteoric diagenesis and incorporated as cinnabar in a palustrine environment, occupying pores and cavities of mammal remains shortly after the degradation of the organic matter (post-mortem enrichment), during the early diagenesis. [ABSTRACT FROM AUTHOR]

A new species of Microdyromys, M. puntarronensis, is described from the Early Oligocene locality Montalbán 8 (Teruel, Spain). It is compared with the other Early Oligocene species of the genus, M. misonnei. The latter is known from Hoogbutsel (Belgium) and Montalbán 1D. Montalbán 8 is intermediate in age between Hoogbutsel and Montalbán 1D, and the dental pattern of its Microdyromys is more advanced than it is in Montalbán 1D. This leads to the conclusion that two lineages of Microdyromys existed in the Early Oligocene. An attempt is made to follow these lineages throughout the Late Oligocene and the Miocene. [ABSTRACT FROM AUTHOR]

Daams & de Bruijn created the subfamily Bransatoglirinae for the genus Bransatoglis Hugueney, and considered Paraglis Baudelot and Oligodyromys Bahlo to be synonyms of Bransatoglis. Twenty two valid species have been classified as Bransatoglis or one of its supposed synonyms, ranging in age from Late Eocene (MP17) to Middle Miocene (MN6) and varying in size from very small to very large. Apparently, Bransatoglis has become a 'wastebasket' and it is impossible to formulate a diagnosis that covers all these species. In this paper the genera Paraglis and Oligodyromys are restored, new diagnoses are given and the genus Microdyromys is transferred from the Dryomyinae to the Bransatoglirinae. A new species of Oligodyromys, O. libanicus, is described from the Lower Oligocene of Montalbán 8 (Teruel, Spain). [ABSTRACT FROM AUTHOR]

A rich and diverse micromammal fauna from the late Turolian (MN13) locality of Negratín-1 (Guadix Basin, southern Spain) is described. The faunal list of this site includes Apodenius gudrunae, Occitanomys alcalai, Stephanomys dubari, Paraethomys meini, Myocricetodon jaegeri, Debruijnimys almenarensis, Apocricetus alberti, Ruscinomys sp., Eliomys sp., Atlantoxerus sp., Parasorex ibericus, and Soricidae indet. This is the most nearly complete mammal fauna from the Miocene of the Guadix Basin and allows precise correlations with localities from other Iberian areas. In addition, some of the taxa identified in Negratín-1 are useful as palaeoecological indicators (Myocricetodon, Debruijnimys, Atlantoxerus), evidencing warm and dry climatic conditions. But the principal interest of the fauna from Negratín-1 is the presence of several species of African origin, the gerbillids Debruijnimys almenarensis and Myocricetodon jaegeri, which are recognized for the first time in Europe. We also ascribe to M. jaegeri the population from the upper Turolian karst infilling of Almenara-M. This finding constitutes new evidence for faunal exchanges between North Africa and the Iberian Peninsula during the Messinian Salinity Crisis. [ABSTRACT FROM AUTHOR]