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The Bølling–Allerød interstadial is the closest warm time period to the Holocene. The study of the climate variability during this most recent warm scenario provides a natural record of potential environmental changes related with global temperature variations. Little is known about this interstadial in the Southern Iberian Peninsula. Therefore, the exceptional climatic record of the Otiñar paleo-lake (ca. 14.5–14.0 cal ka BP), provides environmental information about the first part of this interstadial (Bølling) in this key region. Although the studied high-resolution isotopic record point to almost invariant hydrological conditions in the paleo-lake, with little change in the carbon budget and important limestone dissolution, the pollen record shows an increase in forest species that can be interpreted as a warming trend and an increase in humidity during the Bølling in the area. This record is one of the few continental archives that show this climatic trend in Southern Iberia, agreeing with many other regional records from the western Mediterranean. This does not agree with higher latitude records that show an opposite trend. This opposite pattern in precipitation between the western Mediterranean and more northern latitudes could be explained by a persistent and increasing negative NAO mode during the Bølling in this area.

Detailed pollen, charcoal, isotope and magnetic susceptibility data from an alpine lake sediment core from Sierra Nevada, southern Spain record changes in vegetation, fire history and lake sedimentation since ca. 4100 cal yr BP. The proxies studied record an arid period from ca. 3800 to 3100 cal yr BP characterized by more xerophytic vegetation and lower lake levels. A humid period is recorded between ca. 3100 and 1850 cal yr BP, which occurred in two steps: (1) an increase in evergreen Quercus between 3100 and 2500 cal yr BP, indicating milder conditions than previously and (2) an increase in deciduous Quercus and higher lake levels, between ca. 2500 and 1850 cal yr BP, indicating a further increase in humidity and reduction in seasonal contrast. Humid maxima occurred during the Roman Humid Period, previously identified in other studies in the Mediterranean region. Intensified fire activity at this time could be related to an increase in fuel load and/or in human disturbance. An arid period subsequently occurred between 1850 and 650 cal yr BP, though a decrease in Quercus and an increase in xerophytes. The alternation of persistent North Atlantic Oscillation modes probably played an important role in controlling these humid–arid cycles.

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 includesApodemus gudrunae, Occitanomys alcalai, Stephanomys dubari, Paraethomys meini, Myocricetodon jaegeri, Debruijnimys almenarensis, Apocricetus alberti, Ruscinomyssp.,Eliomyssp.,Atlantoxerussp.,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 gerbillidsDebruijnimys almenarensisandMyocricetodon jaegeri, which are recognized for the first time in Europe. We also ascribe toM. jaegerithe 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.

The Pliocene and Pleistocene continental sedimentary records of the western sector of the Granada Basin, southern Spain, consist of alternating fluvial and lacustrine/palustrine sediments. Two Quaternary sections from this sector have been sampled: Huétor Tájar and Tojaire. They have yielded remains of rodents, insectivores and lagomorphs. The presence in the Huétor Tájar and Tojaire sections of Mimomys, Apodemus atavus, Castillomys rivas and two different species of Allophaiomys, indicates an Early Pleistocene age. These deposits, which are related to a fluvio-lacustrine system, can be differentiated from an older (Pliocene) braided fluvial system. Their dating has important repercussions on the paleogeographic reconstruction of the basin. The conditions inferred from the ecological preferences of the small mammal associations are wet and cold. These associations suggest a predominance of open herbaceous habitats, followed by forested habitats; semiaquatic habitats are the least represented.

The genus Micromys includes a single extant species, Micromys minutus (Pallas, 1771), which lives in Europe and North Asia. This genus is known in the fossil record since the late Miocene; eight fossil species have been described in Europe and Asia, most of them of late Miocene and early Pliocene age. The evolution of this genus during the late Pliocene is barely known. Although it is present in numerous localities of this age, remains of Micromys are usually scarce and generally assigned to the species M. minutus or M. praeminutus Kretzoi, 1959. On the contrary, Micromys is the most abundant genus of Muridae in the late Pliocene locality of Tollo de Chiclana-13 (TCH-13). In a previous paper (Minwer-Barakat et al., 2005), a sample of Micromys from this locality was described, demonstrating its differences from all species of the genus Micromys known until then. Nevertheless, the scarcity of material at that time did not allow the description of a new species. After renewed sampling of this fossiliferous level carried out by the same authors, a more numerous collection is available (41 molars), in which the distinctive features of the new species Micromys caesaris can be observed clearly. The type locality of this new species, Tollo de Chiclana-13, is situated in the central part of the Guadix Basin, an intramontane basin established in the late Miocene. The oldest sedimentary infilling of this basin was deposited in a phase of marine sedimentation during the Tortonian. The upper part of the infilling represents a stage of exclusively continental sedimentation that lasted from latest Tortonian until Late Pleistocene (Viseras, 1991; Fernandez et al., 1996). In the section of Tollo de Chiclana, six fossiliferous localities were described in previous publications (Minwer-Barakat et al., 2004, 2005). These fossiliferous levels, ranging in age from late …

THE GENUS Stephanomys (Muridae, Rodentia) is one of the most common elements in the late Miocene to Early Pleistocene mammal faunas from the Ibero-Occitan region. Its geographic distribution is limited to this area with only two mentions in the late Miocene of Italy (de Giuli, 1989) and Algeria (Coiffait et al., 1985). The genus has been subject of numerous studies, some of them suggesting different interpretations on the phylogenetic relationships between the various described species (Gmelig-Meyling and Michaux, 1973; Cordy, 1978; Adrover, 1986; Bachelet and Castillo-Ruiz, 1990; Aguilar et al., 1993). The most extensive and significant study of the genus is the Ph.D. dissertation of Cordy (1976), who studied in detail several samples of Stephanomys , analyzed the changes observed in successive populations and defined four species ( S. medius , S. michauxi , S. thaleri and S. progressus ), which are considered as nomina nuda because this work was never published. Only one of these species, S. thaleri from the French locality of Seynes, was validated later by Lopez-Martinez et al. (1998). Although invalid, the name Stephanomys progressus has been used by many authors (Gil and Sese, 1984, 1985; Agusti and Galobart, 1986; Agusti et al., 1993a, 1993b; Aguilar et al., 1993; Vianey-Liaud and Michaux, 2003; Furio et al., 2005; Madurell-Malapeira et al., 2009), only some of them referring specifically to it as a nomen nudum (Minwer-Barakat et al., 2005; Laplana and Blain, 2008). This species was considered by Lopez-Martinez et al. (1998) to be a synonym of S. balcellsi . On the contrary, other studies differentiate S. balcellsi from S. progressus , this latter representing the last step of the continuous lineage Progonomys-Stephanomys , an example of increase in size and morphological specialization in relation …