Plinio Montoya

Une faune très diversifiée du Pléistocène inférieur de la Sierra de Quibas (province de Murcia, Espagne)

The Quaternary karstic site of Sierra de Quibas (Abanilla, province of Murcia, Spain) has provided a wide faunal list with more than 60 species. The assemblage of the taxa Arvicola deucalion, Castillomys rivas rivas, Eliomys intermedius, Equus altidens, Capra sp. aff. C. alba and cf. Praeovibos allows the correlation with other Spanish Lower Pleistocene sites in the Betic Cordillera, as Plines 1, Orce 3 and Venta Micena. Therefore Quibas can be located between 1.3 and 1.0 Ma. The palaeoenvironmental features of the area around the karstic cavity and the palaeoclimatic regime are inferred.

Kretzoiarctos gen. nov., the Oldest Member of the Giant Panda Clade

The phylogenetic position of the giant panda, Ailuropoda melanoleuca (Carnivora: Ursidae: Ailuropodinae), has been one of the most hotly debated topics by mammalian biologists and paleontologists during the last century. Based on molecular data, it is currently recognized as a true ursid, sister-taxon of the remaining extant bears, from which it would have diverged by the Early Miocene. However, from a paleobiogeographic and chronological perspective, the origin of the giant panda lineage has remained elusive due to the scarcity of the available Miocene fossil record. Until recently, the genus Ailurarctos from the Late Miocene of China (ca. 8–7 mya) was recognized as the oldest undoubted member of the Ailuropodinae, suggesting that the panda lineage might have originated from an Ursavus ancestor. The role of the purported ailuropodine Agriarctos, from the Miocene of Europe, in the origins of this clade has been generally dismissed due to the paucity of the available material. Here, we describe a new ailuropodine genus, Kretzoiarctos gen. nov., based on remains from two Middle Miocene (ca. 12–11 Ma) Spanish localities. A cladistic analysis of fossil and extant members of the Ursoidea confirms the inclusion of the new genus into the Ailuropodinae. Moreover, Kretzoiarctos precedes in time the previously-known, Late Miocene members of the giant panda clade from Eurasia (Agriarctos and Ailurarctos). The former can be therefore considered the oldest recorded member of the giant panda lineage, which has significant implications for understanding the origins of this clade from a paleobiogeographic viewpoint.

Eucyon debonisi n. sp., a new Canidae (Mammalia, Carnivora) from the latest Miocene of Venta del Moro (Valencia, Spain)

ABSTRACT A new species of canid (Eucyon debonisi n. sp.) is described from the late Miocene of Venta del Moro (Valencia, Spain). The new species is smaller than all the other Eucyon species, excepting E. intrepidus from the late Miocene of Lukeino (Kenya). Eucyon debonisi n. sp. is characterized by the greater size of the M2 in relation with the M1, showing comparable morphology with E. monticinensis, but this new species has a stronger parastyle, a less developed lingual cingulum and a more closed valley in the talon of the M1. Besides, it has a more slender dentition and mandible than E. monticinensis and possesses a diastema between p1 and p2 and between p2 and p3. Excepting the problematic Cants cipio from the middle Turolian locality of Concud (Spain), E. debonisi n. sp. represents the first modern canid that reached western Europe.

Dietary behaviour and competition for vegetal resources in two Early Miocene pecoran ruminants from Central Spain

ABSTRACT Dietary behaviour and competition for resources are investigated for the small-sized ruminants Andegameryx Ginsburg, 1971 and Procervulus Gaudry, 1877 representatives of two largely distinct states of diversification of pecorans. Results obtained from dental microwear and mesowear methodologies are concordant with a mixed feeder strategy for the taxa from the Early Miocene environments of the Iberian Chain (Central Spain). Further, the Spanish taxa investigated had less abrasive diets than their relatives from others similarly aged localities in Europe. This fact raises an important evolutionary uncertainty concerning the traditional characterization of first pecorans as specialized browsers. Instead, data strongly corroborate the recently proposed notion that some Pecora ruminant lineages were able to consume a mixture of browse and grass, and that were originally facultative mixed feeders. However, there is a large degree of variation of their dental wear features. Species were not dependent on a limited type of vegetation and, consequently, were able to exploit different food resources. Dental wear data seem to indicate that these ruminants did not compete for vegetation. In addition, last Andegameryx and earliest Procervulus apparently had a sufficiently different body size to partition the available vegetation in terms of height above ground level to elude competition. Body size difference coupled with an important degree of dietary opportunism may have been factors necessary for their coexistence.

Paracamelichnum Jumillensis n.ichnogen. n.ichnosp., Upper Miocene Camelidae Ichnites from the Hoya de la Sima site (Murcia, Spain)

In the proximity of Jumilla (Murcia, Spain) there is a site called Hoya de la Sima with mammal footprints dating from the Upper Miocene. This site is an old gypsum quarry where footprints of Hipparion, Pecoripeda, Carnivora, Ursidae, and Proboscidea were discovered. While the site was being cleaned and conditioned after the discovery to protect the prints, Camelidae and other prints were unearthed and are currently being studied. The description of the Camelidae ichnites demonstrates that these belong to a new ichnogenera, produced by the prints of Paracamelus. The grouping of trackways is congruent with the gregariousness of these animals and with the concentration observed in similar sites.

Tracing the origin of the panda’s thumb

We investigate the relative development of the carnivoran radial sesamoids to untangle the evolution of this iconic structure. In the pandas (both giant and red), this ‘false thumb’ is known to perform a grasping role during bamboo feeding in both the red and giant pandas. An original locomotor role has been inferred for ailurids, but this remains to be ascertained for ursids. A large sample of radial sesamoids of Indarctos arctoides from the Miocene of Batallones-3 (Spain) indicates that this early ailuropodine bear displayed a relatively hypertrophied radial sesamoid, with a configuration more similar to that of the red panda and other carnivorans than to that of giant pandas. This false thumb is the first evidence of this feature in the Ursidae, which can be linked to a more herbivorous diet. Moreover, in the two extant pandas, the false thumb should not be interpreted as an anatomical convergence, but as an exaptive convergence regarding its use during the bamboo feeding, which changes the evolutionary view of this singular structure.

Mio-Pliocene rodent assemblages from Alcoi Forn (Alcoy Basin, Eastern Spain). Biostratigraphical and palaeoclimatical inferences

Abstract In this work, we describe four new micromammal sites in the northern side of the Gormaget ravine, in the Alcoy Basin (Spain): AF-1’06, AF-1’07, AF-1A and AF-2. Based on the study of the faunal remains from these localities, we infer a latest Turolian-earliest Ruscinian age for AF-1’06 and AF-1A, and an earliest Ruscinian age for AF-1’07 and AF-2. The species assemblage of the locality AF-1’06, the only one which have yielded a sufficient number of remains to perform a palaecological analysis, shows warm and dry conditions near the Mio-Pliocene boundary in the Alcoy Basin. These data show a reduction of dry and warm indicators from older to younger localities in the Alcoy Basin, suggesting a change to colder and more humid conditions during the Early Pliocene.

Apocricetus barrierei (Rodentia, Mammalia) from La Bullana 2B and La Bullana 3 (Cabriel Basin, Valencia, Spain). Revision of the Late Miocene–Early Pliocene forms of the genus Apocricetus

Apocricetus Freudenthal et al. (Treballs del Museu de Geologia de Barcelona 7: 11–93, 1998) is a medium to large Cricetinae, practically without mesolophids in the m1 and m2, with long third molars; anterior and posterior protolophule are present and the posterior metalophule is reduced or absent. Apocricetusbarrierei (Mein and Michaux Comptes Rendus Academie de Sciences de Paris D 270: 2780–2783, 1970) was defined on the basis of three specimens from the French locality Chabrier. Apart from this site, several French and Spanish localities of Early Pliocene age contain remains of this species. Despite this extra material, the species is poorly characterized, and none of the localities contains material of all six dental elements. In this paper, two new assemblages from La Bullana 2B and La Bullana 3 (Cabriel Basin, Spain) are described. The rich assemblage from La Bullana 2B provides a better insight in the metrical and morphological variability of this species.KurzfassungApocricetus Freudenthal et al. (Treballs del Museu de Geologia de Barcelona 7: 11–93, 1998) ist eine mittelgrosze bis grosze Cricetine, fast ohne Mesolophid in m1 und m2, lange dritte Molaren; vorderer und hinterer Protolophulus und hinterer Metalophulus reduziert oder fehlend. Apocricetusbarrierei (Mein and Michaux Comptes Rendus Academie de Sciences de Paris D 270: 2780–2783, 1970) gründet sich auf drei Zähnen aus der Französischen Lokalität Chabrier. Daneben ist sie dokumentiert in verschiedenen Französischen and Spanischen frühpliozänen Fundstellen. Die Art ist mangelhaft charakterisiert und keine seiner Fundstellen enthält Material von allen sechs Zahnpositionen. In dieser Arbeit beschreiben wir zwei neue Populationen aus La Bullana 2B und La Bullana 3 (Cabriel Becken, Spanien). Die reiche Aufsammlung aus La Bullana 2B erlaubt eine bessere Einsicht in die metrische and morphologische Variabilität dieser Art.

On the Socio-Sexual Behaviour of the Extinct Ursid Indarctos arctoides: An Approach Based on Its Baculum Size and Morphology

The fossil bacula, or os penis, constitutes a rare subject of study due to its scarcity in the fossil record. In the present paper we describe five bacula attributed to the bear Indarctos arctoides Depéret, 1895 from the Batallones-3 site (Madrid Basin, Spain). Both the length and morphology of this fossil bacula enabled us to make interpretative approaches to a series of ecological and ethological characters of this bear. Thus, we suggest that I. arctoides could have had prolonged periods of intromission and/or maintenance of intromission during the post-ejaculatory intervals, a multi-male mating system and large home range sizes and/or lower population density. Its size might also have helped females to choose from among the available males.

Suoidea (Mammalia) fromthe Lower Miocene locality of Buñol, Valencia, Spain

Abstract The Lower Miocene (MN 4, zone C of the Aragonian) locality of Bunol yielded fossils of the followingSuoidea: Taucanamo aff. sansaniense (Palaeochoeridae), Aureliachoerus aurelianensis and Bunolistriodon lockharti (Suidae), as well as some problematic fossils that resemble Propotamochoerus and that are assigned to Suinae? indet. The Taucanamo from Bunol represents one of the oldest records of the genus. The distribution of this genus is particular in that it is abundant in France and it is known from Catalonia and Valencia, but not known from the many localities of the interior of Spain. The association of Taucanamo, Aureliachoerus and Bunolistriodon is common in France in MN 4 and 5 and suggests a similar environment. The Suinae? indet. from Bunol presents possibly the oldest known representative of this subfamily. The oldest certain record of Suinae in Europe is Propotamochoerus palaeochoerus in the latest Aragonian. The oldest record in the Indian Subcontinent is in the lower Chinji Formation, but these Suinae are much smaller than the animal from Bunol. They are also considerably later. These fossils from Bunol appear to be geographically and/or stratigraphically isolated from other records of early Suinae.