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Mammalia
Selected AbstractsA NEW MICROCHOERINE OMOMYID (PRIMATES, MAMMALIA) FROM THE ENGLISH EARLY EOCENE AND ITS PALAEOBIOGEOGRAPHICAL IMPLICATIONSPALAEONTOLOGY, Issue 3 2007J. J. HOOKER Abstract:, A new genus and species of omomyid primate, Melaneremia bryanti, is described from the Early Eocene Blackheath Beds of Abbey Wood, London, UK. It shares unique derived characters with the European subfamily Microchoerinae and is its most primitive member. It is nevertheless more derived than the primitive omomyid Teilhardina belgica from the beginning of the European Eocene. Cladistic analysis shows that the Microchoerinae are sister group to a clade comprising subfamilies Omomyinae and Anaptomorphinae, but excluding Teilhardina belgica and T. asiatica, which are stem omomyids. The Mammalian Dispersal Event (MDE), which marks the beginning of the Eocene (55·8 Ma), saw the dispersal of primates, perissodactyls and artiodactyls into the Northern Hemisphere. At this time similar species of Teilhardina lived in Europe, Asia and North America. The Abbey Wood microchoerine lived about 1 million years later. It co-occurs with non-primate species identical or very similar to those that lived in North America. The latter were ground-dwellers, whereas the microchoerine and others that show distinct differences from North American relatives were tree-dwellers. Land-bridges connected North America and Europe via Greenland at the beginning of the Eocene, but 2 million years later these had been severed by submarine rifting. North American species at Abbey Wood indicate that a land connection still remained at c. 55 Ma. However, the forest belt that must have been continuous during the MDE to allow tree-dwellers to disperse between the continents is likely by this time to have been disrupted, perhaps by volcanic eruption. [source] Morphological variation of the five vole species of the genus Microtus (Mammalia, Rodentia, Arvicolinae) occurring in GreeceACTA ZOOLOGICA, Issue 3 2009Stella E. Fraguedakis-Tsolis Abstract Morphometric data for the five vole species of the genus Microtus living in Greece are old, sparse, poor and insufficiently analysed. This work aims to give the first comprehensive morphometric analysis of body and skull inter- and intraspecific variation for M. (M.) guentheri, M. (M.) rossiaemeridionalis, M. (Terricola) subterraneus, M. (T.) felteni and M. (T.) thomasi, applying multivariate statistics to 28 linear morphometric variables. It was based on ample material (202 adult individuals) using samples from localities that adequately cover the entire distributional range of each species in Greece. The five species and the two subgenera (Microtus and Terricola) were morphometrically clearly distinguished and discriminating variables were revealed. However, morphometrics did not provide robust criteria to infer phylogenetic relations among species. Furthermore, three species, M. (M.) guentheri, M. (M.) rossiaemeridionalis and M. (T.) thomasi, exhibited considerable intraspecific size or shape variation, which was mostly random and not associated with geographical proximity. Comparisons with data in the literature, mainly concerning populations of these species from adjacent areas, indicate that the Greek M. (M.) guentheri, M. (M.) rossiaemeridionalis and M. (T.) thomasi tend to be smaller than their conspecifics, while M. (T.) subterraneus and M. (T.) felteni are about equal in size to their Balkan relatives. [source] Fore limb bones of late Pleistocene dwarf hippopotamuses (Mammalia, Cetartiodactyla) from Madagascar previously determined as belonging to the crocodylid Voay Brochu, 2007FOSSIL RECORD-MITTEILUNGEN AUS DEM MUSEUM FUER NATURKUNDE, Issue 2 2010Oliver Hampe Abstract A humerus and two radii of juvenile dwarf hippopotamuses are redescribed. The subfossil bones from the collection of the Museum für Naturkunde Berlin were erroneously assigned to the horned crocodile Voay robustus (Grandidier & Vaillant, 1872) by Bickelmann & Klein (2009). All three limb bones presented here belong to immature animals. The epiphyses are not fused, except the proximal extremity of the right radius; and the radius and ulna are also unfused. The two radii are from individuals of different size, whereas the left radius and the humerus are from animals of similar size. Morphologically, the limb bones cannot be identified to species level. A tentative assignment to Hippopotamus madagascariensis is discussed based on the knowledge of the geographic origin on the island. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] The first complete skeleton of Megaloceros verticornis (Dawkins, 1868) Cervidae, Mammalia, from Bilshausen (Lower Saxony, Germany): description and phylogenetic implicationsFOSSIL RECORD-MITTEILUNGEN AUS DEM MUSEUM FUER NATURKUNDE, Issue 1 2002Thekla Pfeiffer Abstract The first well preserved, articulated skeleton of a young male deer of Megaloceros verticornis (Dawkins, 1868) was excavated from early Middle Pleistocene sediments of the clay pit of Bilshausen (Unter-Eichsfeld, Lower Saxony). This find made it possible, for the first time, to establish, using cladistic techniques, the systematic position of Megaloceros verticornis among Pleistocene and Holocene plesiometacarpal and telemetacarpal cervids. By contrast to the antler and tooth characters, the postcranial characters, in particular, are suitable for phylogeny reconstruction. Megaloceros verticornis from Bilshausen shows great similarity with M. giganteus of the Upper Pleistocene of Europe in its skeletal morphology, and bootstrap values (BP = 100) show strong support for the monophyly of M. giganteus and M. verticornis. The analysis yields no evidence, however, of a close relationship between Dama and Megaloceros, which has been widely discussed in the literature because of the presence of large, palmated antlers in both genera. Aus der Tongrube von Bilshausen (Unter-Eichsfeld, Niedersachsen) konnte das erste, vollständige Skelett eines jugen Hirsches von Megaloceros verticornis (Dawkins, 1868) aus mittelpleistozänen Sedimentablagerungen geborgen werden. Dieser Fund ermöglichte es erstmalig, die systematische Stellung von Megaloceros verticornis im System plesiometacarpaler und telemetacarpaler Hirsche des Pleistozäns und Holozäns auf breiter Basis zu untersuchen. Im Gegensatz zu den Geweih- und Zahnmerkmalen eignen sich die postcranialen Merkmale des Skelettes besonders gut für eine phylogenetische Rekonstruktion der Hirsche. Die Gemeinsamkeit Großer Schaufelgeweihe bei Dama dama und dem Riesenhirsch Megaloceros giganteus hat dazu geführt, beide in eine enge phylogenetische Beziehung zu setzen, was in der Literatur zu einer anhaltenden Kontroverse geführt hat. Die Analyse der Morphologie der postcranialen Elemente zeigt jedoch, dass es keine enge Verwandtschaft zwischen Dama und Megaloceros gibt. [source] Masticatory muscle architecture in the Laotian rock rat Laonastes aenigmamus (Mammalia, Rodentia): new insights into the evolution of hystricognathyJOURNAL OF ANATOMY, Issue 4 2009Lionel Hautier Abstract We present the first descriptive comparison of the skull, mandible and jaw muscles of the recently recovered Laotian rock rat Laonastes aenigmamus. The gross anatomy of five specimens captured in Laos and internal architecture of the jaw musculature were studied using dissections. The following muscles are described: temporal, masseter, pterygoids, digastric, mylohyoid, geniohyoid and transverse mandibular. The description of the masticatory apparatus of L. aenigmamus offers a rare opportunity to assess the order of establishment of the morphological characters during the evolution of Ctenohystrica. Striking convergences have occurred during the evolution of Diatomyidae and L. aenigmamus presents a unique combination of myological features that corresponds to a mixture of sciurognathous and hystricognathous characters. If L. aenigmamus is a sciurognathous rodent, we have to assume that it independently acquired a pars reflexa of the superficial masseter. We show for the first time that the development of this pars reflexa has occurred several times during the evolution of Ctenohystrica and can no longer be considered a synapomorphic feature of ,Hystricognathi'. These results bring new insights into the evolution of hystricognathy and have profound implications for the interpretation of the fossil record of early hystricognath rodents. [source] The evolution of orbit orientation and encephalization in the Carnivora (Mammalia)JOURNAL OF ANATOMY, Issue 5 2009John A. Finarelli Abstract Evolutionary change in encephalization within and across mammalian clades is well-studied, yet relatively few comparative analyses attempt to quantify the impact of evolutionary change in relative brain size on cranial morphology. Because of the proximity of the braincase to the orbits, and the inter-relationships among ecology, sensory systems and neuroanatomy, a relationship has been hypothesized between orbit orientation and encephalization for mammals. Here, we tested this hypothesis in 68 fossil and living species of the mammalian order Carnivora, comparing orbit orientation angles (convergence and frontation) to skull length and encephalization. No significant correlations were observed between skull length and orbit orientation when all taxa were analysed. Significant correlations were observed between encephalization and orbit orientation; however, these were restricted to the families Felidae and Canidae. Encephalization is positively correlated with frontation in both families and negatively correlated with convergence in canids. These results indicate that no universal relationship exists between encephalization and orbit orientation for Carnivora. Braincase expansion impacts orbit orientation in specific carnivoran clades, the nature of which is idiosyncratic to the clade itself. [source] The highly specialized vocal tract of the male Mongolian gazelle (Procapra gutturosa Pallas, 1777 , Mammalia, Bovidae)JOURNAL OF ANATOMY, Issue 5 2003R. Frey Abstract The entire head and neck of a wild adult male Mongolian gazelle (Procapra gutturosa) was dissected with special reference to its enlarged larynx. Two additional adult male specimens taken from the wild were analysed by computer tomography. The sternomandibularis, omohyoideus, thyrohyoideus and hyoepiglotticus muscles are particularly enlarged and improve laryngeal suspension and stabilization. The epiglottis is exceptionally large. A permanent laryngeal descent is associated with the evolution of an unpaired palatinal pharyngeal pouch. A certain momentary descent seems to occur during vocalization. The high lateral walls of the thyroid cartilage are ventrally connected by a broad keel. The large thyroarytenoid muscle is divided into two portions: a rostral ventricularis and a caudal vocalis muscle. A paired lateral laryngeal ventricle projects between these two muscles. The massive vocal fold is large and lacks any rostrally directed flexible structures. It is supported by a large cymbal-like fibroelastic pad. Vocal tract length was measured in the course of dissection and in computer tomographic images. Two representative spectrograms, one of an adult male and one of a juvenile, recorded in the natural habitat of the Mongolian gazelle are presented. In the spectrograms, the centre frequency of the lowest band is about 500 Hz in the adult male and about 790 Hz in the juvenile. The low pitch of the adult male's call is ascribed to the evolutionary mass increase and elongation of the vocal folds. In the habitat of P. gutturosa a call with a low pitch and, thus, with an almost homogeneous directivity around the head of the vocalizing animal may be optimally suited for multidirectional advertisement calls during the rut. The signal range of an adult male's call in its natural habitat can therefore be expected to be larger than the high-pitched call of a juvenile. [source] Why is there discordant diversity in sengi (Mammalia: Afrotheria: Macroscelidea) taxonomy and ecology?AFRICAN JOURNAL OF ECOLOGY, Issue 1 2009Galen B. Rathbun Abstract The seventeen species of sengis or elephant-shrews form a well-defined clade of mammals endemic to Africa that occupy the extremes of terrestrial habitats, from coastal deserts to montane forests. Because of their isolation on Africa soon after the break-up of Gondwanaland, theoretically sengis initially evolved with little competition from other placental radiations. Their life history features include myrmecophagy, saltatorial gaits, no or limited use of nests, social monogamy, small litters of precocial young and absentee maternal care of neonates. These traits together are unique to the Macroscelidea and represent a wedding of features usually associated with either small antelopes or anteaters. Combined, these features define an adaptive syndrome that presumably has been relatively immune to competition from contemporary mammals, partially due to phylogenetic inertia. Yet paradoxically, the syndrome is well suited to a wide range of terrestrial habitats, resulting in low taxonomic diversity. Because of their unusual phylogeny and low species diversity, conservation interest is high for those sengis with relatively low densities in fragmented forests. Résumé Les 17 espèces de sengis (musaraignes éléphants) forment un clade bien déterminé de mammifères endémiques d'Afrique, qui occupe des habitats terrestres extrêmes allant de déserts côtiers à des forêts de montagne. En raison de leur isolement sur le continent africain très vite après la scission du Gondwana, les sengis ont théoriquement évolué au départ sans qu'il existe beaucoup de compétition avec les radiations d'autres placentaires. Les caractéristiques de leur histoire incluent de la myrmécophagie, des déplacements par bonds, un usage de nids limité, voire inexistant, la monogamie sociale, de petites portées de jeunes précoces et l'inexistence de soins maternels pour les nouveau-nés. Toutes ces caractéristiques sont uniques pour les Macroscélidés et représentent un regroupement de caractéristiques d'habitude associées à de petites antilopes ou à des fourmiliers. Combinées, ces caractéristiques définissent un syndrome d'adaptation qui, sans doute, fut relativement protégé de toute compétition avec des mammifères contemporains, à cause, en partie, de l'inertie phylogénétique. Mais, paradoxalement, ce syndrome est bien adaptéà une vaste gamme d'habitats terrestres, ce qui n'entraîne donc qu'une faible diversité taxonomique. En raison de leur phylogenèse inhabituelle et de la faible diversité entre ces espèces, l'intérêt de la conservation est considérable pour ces sengis dont la densité, dans des forêts fragmentées, est relativement faible. [source] Evolution of the middle ear apparatus in talpid molesJOURNAL OF MORPHOLOGY, Issue 6 2006Matthew J. Mason Abstract The middle ear structures of eight species of mole in the family Talpidae (Mammalia: Eulipotyphla) were studied under light and electron microscopy. Neurotrichus, Parascalops, and Condylura have a simple middle ear cavity with a loose ectotympanic bone, ossicles of a "microtype" morphology, and they retain a small tensor tympani muscle. These characteristics are ancestral for talpid moles. Talpa, Scalopus, Scapanus, and Parascaptor species, on the other hand, have a looser articulation between malleus and ectotympanic bone and a reduced or absent orbicular apophysis. These species lack a tensor tympani muscle, possess complete bullae, and extensions of the middle ear cavity pneumatize the surrounding basicranial bones. The two middle ear cavities communicate in Talpa, Scapanus, and Parascaptor species. Parascaptor has a hypertrophied malleus, a feature shared with Scaptochirus but not found in any other talpid genus. Differences in middle ear morphology within members of the Talpidae are correlated with lifestyle. The species with middle ears closer to the ancestral type spend more time above ground, where they will be exposed to high-frequency sound: their middle ears appear suited for transmission of high frequencies. The species with derived middle ear morphologies are more exclusively subterranean. Some of the derived features of their middle ears potentially improve low-frequency hearing, while others may reduce the transmission of bone-conducted noise. By contrast, the unusual middle ear apparatus of Parascaptor, which exhibits striking similarities to that of golden moles, probably augments seismic sensitivity by inertial bone conduction. J. Morphol. © 2006 Wiley-Liss, Inc. [source] Sperm head morphology in 36 species of artiodactylans, perissodactylans, and cetaceans (Mammalia)JOURNAL OF MORPHOLOGY, Issue 2 2005Amy Downing Meisner Abstract Detailed descriptions of mammalian sperm morphology across a range of closely related taxa are rare. Most contributions have been generalized descriptions of a few distantly related mammalian species. These studies have emphasized a generalized ungulate sperm morphology, but have not underscored several important morphological differences in ungulate sperm, such as head shape. The present study is the first to document descriptions of sperm head morphology using cold field-emission scanning electron microscopy (FE-SEM) for a large number of closely related mammalian species. In total, the sperm of 36 species in three orders: Artiodactyla (even-toed ungulates), Cetacea (whales, porpoises, and dolphins), and Perissodactyla (odd-toed ungulates) were examined to gather new information relevant to the debate about the phylogenetic placement of cetaceans relative to terrestrial ungulates. In all species examined, the sperm heads were generally flattened and ovate in shape with a distinct apical ridge, although considerable variation in sperm head shape was detected, both within and between orders. In artiodactylans, the sperm head was uniformly flat in lateral view, whereas perissodactylan and cetacean sperm heads showed a distinct posterior thickening. In both artiodactylans and perissodactylans, the mitochondria were elongate and wound in a tight helix around the midpiece, whereas in cetaceans the mitochondria were rounded and appeared to be randomly arranged around the midpiece. Additionally, prominent ridges running along the anterior,posterior axis were observed in the postacrosomal region of the sperm head in four species of cetaceans. These ridges were not observed in any of the terrestrial ungulates examined. Pits or fenestrations were detected in the postacrosomal region in most artiodactylan species examined; these structures were not detected in perissodactylans or cetaceans. The equatorial segment of the acrosome was detected in the artiodactylan species examined, tentatively identified in perissodactylans, but not found in cetaceans. Its shape and location are described for relevant taxa. The presence of a recently reported substructure within the equatorial segment (the equatorial subsegment; Ellis et al. [2002] J Struct Biol 138:187,198) was detected in artiodactylans, and its shape is described for the species examined. © 2004 Wiley-Liss, Inc. [source] New data on the distribution and genetic structure of Greek moles of the genus Talpa (Mammalia, Talpidae)JOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 2 2010G. A. Tryfonopoulos Abstract In this work, we employed molecular markers and confirmed the occurrence of two mole species, Talpa stankovici and Talpa europaea in Greece. For the first species, all analyses revealed three major phylogroups, exhibiting great genetic divergence, possibly due to a vicariant event. This event was probably the Peloponnisos' insulation during the Pliocene and the following sea level fluctuations. A scenario of stable, large-sized populations for a long period rather than rapid growth from small-sized populations or founder events is supported. Additionally, T. stankovici's distribution area is extended to a southernmost limit. For T. europaea there is evidence of low genetic divergence between Greek and Central and North European populations. [source] Additional data on early Paleocene metatherians (Mammalia) from Punta Peligro (Salamanca Formation, Argentina): comments based on petrosal morphologyJOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 4 2009A. M. Forasiepi Abstract Metatherian remains from Punta Peligro (Chubut Province, Argentina; Salamanca Formation, early Paleocene) are scarce, but at present, there are at least four different taxa known by dental remains. We describe here an incomplete petrosal showing metatherian affinities. Among the dentally known taxa from the same stratigraphic levels, the overall size of the petrosal fits that predicted for Derorhynchus, which in turn was assigned to the order Didelphimorphia. The features of the petrosal we describe do not correspond with the morphology observed among didelphoid marsupials, the only members of Didelphimorphia with well known basicrania, suggesting that if the association of petrosal and dental remains is correct, then referral of Derorhynchus to the Didelphimorphia has to be revised. The taxonomic content of this group of marsupials, as presently interpreted, represents a paraphyletic or polyphyletic grouping of metatherians. Resumen Datos adicionales sobre los metaterios (Mammalia) del Paleoceno Temprano de Punta Peligro (Formación Salamanca, Argentina): comentarios basados en la morfología del petroso. Restos de metaterios de Punta Peligro (Provincia de Chubut, Argentina: Formación Salamanca, Paleoceno Temprano) son aun escasos; actualmente existen, al menos, cuatro taxa diferentes, reconocidos por su dentición. En esta contribución, describimos un petroso incompleto referido a un metaterio. Entre los taxa reconocidos previamente para estos niveles estratigráficos a partir de dientes, el tamaño del petroso, en general, concuerda con el estimado para Derorhynchus, quien a su vez, fue referido al Orden Didelphimorphia. Los rasgos del petroso, sin embargo, no corresponden con la morfología observada entre los miembros vivientes de este grupo (i.e. marsupiales Didelphoidea), sugiriendo que, si la asociación propuesta es correcta, entonces, la asignación de Derorhynchus a los Didelphimorphia debiera ser revisada. El contenido taxonómico actual de este grupo de marsupiales pareciera ser más probablemente un grupo artificial de metaterios, como fuera sugerido previamente por otros autores. [source] Genetic diversity of captive binturongs (Arctictis binturong, Viverridae, Carnivora): implications for conservationJOURNAL OF ZOOLOGY, Issue 4 2007L. Cosson Abstract The binturong Arctictis binturong is a threatened carnivore (Mammalia) that ranges throughout the forests of South-east Asia. This study evaluates the genetic diversity of captive binturong populations in European zoos and attempts to assess their geographic origin. We sequenced the hypervariable region 1 of the mitochondrial control region of 56 binturongs, among which 20 had a known geographic origin. We showed that at least two distinct geographic clades exist and were able to assess the geographic clade to which captive individuals belong. Moreover, a low genetic diversity was observed among the captive population of European zoos. Although our results are preliminary, zoo managers should consider the evolutionary significant units identified by this study, and which correspond to recognized sub-species, when planning binturong reproduction programs. [source] Molecular phylogenetics of soricid shrews (Mammalia) based on mitochondrial cytochrome b gene sequences: with special reference to the SoricinaeJOURNAL OF ZOOLOGY, Issue 1 2006S. D. Ohdachi No abstract is available for this article. [source] Bite forces, canine strength and skull allometry in carnivores (Mammalia, Carnivora)JOURNAL OF ZOOLOGY, Issue 2 2005Per Christiansen Abstract Skull variables were analysed for allometry patterns in 56 species of extant carnivores. As previously reported, many skull variables scale near isometrically with either skull length or lower jaw length. The maximal gape angle scales insignificantly (P<0.05) with skull size, but the clearance between the canines shows a significant relationship with skull size and scales near isometrically. Maximal bite forces were estimated from geometrical cross-sectional areas of dried skulls, and the bending strength of the canines was computed by modelling the canines as a cantilevered beam of solid, homogeneous material with an elliptical cross section. Previous hypotheses of large taxon differences in canine bending strengths, so that felids have stronger canines than canids, are corroborated when actual bite forces at the upper canine are ignored. Incorporation of bite force values, however, nullifies the differences in canine bending strength among felids and canids, and ursids seem to have stronger canines than felids. This is probably because of the significantly longer canines of felids compared to canids and ursids, and the generally high bite forces of felids. [source] A species-level phylogenetic supertree of marsupialsJOURNAL OF ZOOLOGY, Issue 1 2004Marcel Cardillo Abstract Comparative studies require information on phylogenetic relationships, but complete species-level phylogenetic trees of large clades are difficult to produce. One solution is to combine algorithmically many small trees into a single, larger supertree. Here we present a virtually complete, species-level phylogeny of the marsupials (Mammalia: Metatheria), built by combining 158 phylogenetic estimates published since 1980, using matrix representation with parsimony. The supertree is well resolved overall (73.7%), although resolution varies across the tree, indicating variation both in the amount of phylogenetic information available for different taxa, and the degree of conflict among phylogenetic estimates. In particular, the supertree shows poor resolution within the American marsupial taxa, reflecting a relative lack of systematic effort compared to the Australasian taxa. There are also important differences in supertrees based on source phylogenies published before 1995 and those published more recently. The supertree can be viewed as a meta-analysis of marsupial phylogenetic studies, and should be useful as a framework for phylogenetically explicit comparative studies of marsupial evolution and ecology. [source] Distribution, status and conservation problems of the Spanish Ibex, Capra pyrenaica (Mammalia: Artiodactyla),MAMMAL REVIEW, Issue 1 2002Jesús M. Pérez ABSTRACT In this paper, the distribution and status of the Spanish Ibex, Capra pyrenaica (Mammalia: Artiodactyla), are revised. The whole Iberian population numbers nearly 50 000, distributed in more than 50 nuclei, and has generally increased during the last decades. Nevertheless, within this wider context, different conditions apply to different populations, including recent extinction (the Pyrenean population), recovery from recent severe epizooty of sarcoptic mange (e.g. the Sierras de Cazorla and Segura y Las Villas range population) and populations at high densities (e.g. Gredos mountain range and Sierra de Grazalema Natural Park, among others). The main factors affecting the conservation of this species are also reported and discussed. On the basis of current information we propose the status of ,vulnerable' for the Spanish Ibex. [source] Identification of the endangered small red brocket deer (Mazama bororo) using noninvasive genetic techniques (Mammalia; Cervidae)MOLECULAR ECOLOGY RESOURCES, Issue 3 2009SUSANA GONZÁLEZ Abstract The small red brocket deer Mazama bororo is one of the most endangered deer in the Neotropics. The great morphological similarities with three other sympatric brocket deer species, coupled with the fact that they inhabit densely forested habitats complicate detection and prevent the use of traditional methodologies for accurate identification of species. The ability to determine the presence of this endangered species in an area is crucial for estimating its distribution range, and is critical for establishing conservation management strategies. Here we describe a fast and reliable noninvasive genetic method for species identification of Mazama species from faeces. We designed a primer set that amplifies a short 224-bp fragment of the cytochrome b and demonstrate its effectiveness in successful amplification of DNA isolated from both tissue and faecal samples. This fragment contains a BSTNI/ECORII digestion site that is unique to the endangered M. bororo. The digested polymerase chain reaction products yielded a 160-bp fragment that is clearly visible in a 2% agarose gel. Two other diagnostic sites were identified to differentiate the other three sympatric species, SspI (M. gouazoubira) and AflIII (M. americana, and M. nana). [source] A new genus of rodents (Remyidae, Mammalia) from the Iberian EocenePALAEONTOLOGY, Issue 1 2010RAMÓN QUER Abstract:, In this article, a new genus, Frontanyamys, is defined based on the new species F. russelli. The genus is recorded from the lower Upper Eocene (Bartonian) beds AT Sant Jaume de Frontanya (NE Spain). This genus shows clear affinities with the previously described genera Zamoramys, Remys and Pairomys. They are therefore assembled in the family Remyidae (new rank). The remyids are characterised by the precocious development of high-crowned molars and retain a morphologically primitive dental pattern. The oldest remyids are found in the middle Eocene of Spain (Zamoramys) and are probably derived from a morphologically primitive protrogomorph rodent such as Corbarimys paisi. The last representatives of the family such as Remys and Pairomys developed a fully lophodont dental pattern. [source] A NEW SPECIES OF DICERORHINUS (RHINOCEROTIDAE) FROM THE PLIO-PLEISTOCENE OF MYANMARPALAEONTOLOGY, Issue 6 2008ZIN-MAUNG-MAUNG-THEIN Abstract:, A skull and mandible of the new species Dicerorhinus gwebinensis sp. nov. of Rhinocerotidae (Mammalia, Perissodactyla) is described. The material is collected from the upper part of the Irrawaddy sediments (Plio-Pleistocene) in central Myanmar. D. gwebinensis sp. nov. is morphologically more similar to the extant species D. sumatrensis (Sumatran rhinoceros) than to other species of the genus but differs from D. sumatrensis in having the comparatively shorter nasal, the more concave dorsal profile of the skull, the more elevated occiput and presence of molar crista in M3/. This is the first discovery of Dicerorhinus in the upper Miocene to lower Pleistocene of the Indian subcontinent and Mainland Southeast Asia, and fills the chronological and geographical gap of this lineage in Asia. The Dicerorhinus clade probably migrated into Southeast Asia from East Asia by the Pliocene or early Pleistocene. This hypothesis is supported by the scarcity or absence of this clade in the Neogene mammalian fauna of the Indian Subcontinent. [source] The origin of chalicotheres (Perissodactyla, Mammalia)PALAEONTOLOGY, Issue 6 2004J. J. Hooker Description of a new genus of perissodactyl, Protomoropus, for the species ,Hyracotherium'gabuniai Dashzeveg and its inclusion with a diversity of other primitive perissodactyls in a cladistic analysis results in the following higher order changes to our knowledge of perissodactyl phylogeny. Protomoropus is sister taxon to the Chalicotheriidae plus Lophiodontidae, which themselves are confirmed as sister groups. The previously monofamilial superfamily Chalicotherioidea is extended to include all three taxa. Paleomoropus and Lophiaspis are shown to be primitive lophiodontids. Various genera of the Isectolophidae are shown to be stem members of a clade that includes chalicotheres and lophiodonts. The infraorder Ancylopoda is extended to include them. Inclusion of isectolophids in the Ancylopoda rather than as stem tapiromorphs results in the break up of the clade Tapiromorpha. Instead, the modern perissodactyl groups, comprising the horse superfamily Equoidea and that of the rhinos and tapirs, the Ceratomorpha (here reduced in rank to parvorder), form a new clade which is here named infraorder Euperissodactyla nov. The Brontotheriidae form the sister group to Ancylopoda plus Euperissodactyla. The clade comprising Ancylopoda plus Euperissodactyla is named suborder Lophodontomorpha nov. The Chalicotherioidea and Chalicotheriidae evolved in Asia. The Lophiodontidae arose following dispersal from Asia to North America. Dispersal continued to Europe, where the family radiated. [source] A new species of Karydomys (Rodentia, Mammalia) and a systematic re-evaluation of this rare Eurasian Miocene hamsterPALAEONTOLOGY, Issue 6 2004Thomas Mörs We describe a new species of the rare and enigmatic cricetid genus Karydomys from the middle Miocene Ville Formation of the Hambach lignite mine in north-west Germany. The locality Hambach 6C has yielded the first substantial records of Karydomys from central Europe. For the first time, all molar positions are well-documented, including the previously unknown m2. The excellent molar material allows us to distinguish Karydomys wigharti sp. nov. from the western European species K. zapfei. Karydomys wigharti predominantly occurs at localities that are correlated with the upper part of the Mammalian Neogene biozone MN 5. The new finds are of palaeobiogeographic significance for the genus Karydomys, since Hambach 6C represents the north-westernmost outpost of terrestrial Miocene faunas in Europe. In addition, the locality has yielded the first lower jaws and incisors of the genus. Both the jaw morphology, and the ornamentation and microstructure of the incisor enamel offer new arguments for a systematic classification of Karydomys into the subfamily Democricetodontinae. We assume that the scarcity of the two large European Karydomys species can be explained by their special adaptation to wet habitats, which are poorly documented in the fossil record. [source] A New Species of Amphirhagatherium (Choeropotamidae, Artiodactyla, Mammalia) from the Late Eocene Headon Hill Formation of Southern England and Phylogeny of Endemic European ,anthracotherioids'PALAEONTOLOGY, Issue 5 2001Jerry J. Hooker A new species of artiodactyl, Amphirhagatheriumedwardsi sp. nov., is described from the Late Eocene (Priabonian) Headon Hill Formation of the Hampshire Basin, southern England. The Haplobunodontidae, in which Amphirhagatherium is usually placed, has recently been combined with the monotypic Choeropotamidae, both essentially European endemic families. New anatomical information is forthcoming from both the new species and recently published data on related species. A cladistic analysis of taxa included in the two families, the possible anthracotheriid Thaumastognathus and the enigmatic Tapirulus, was conducted to test the relationships implied by observed morphological similarities. The genus Anthracobunodon is shown to be paraphyletic and is here synonymized with Amphirhagatherium. Choeropotamus and Thaumastognathus are sister taxa nested with three species of Haplobunodon and Haplobunodon is paraphyletic and polyphyletic, but this clade is too weakly resolved internally for reliable taxonomic changes. LophiobunodonTapirulus are sister taxa nested with a fourth species of Haplobunodon. The synonymy of the Haplobunodontidae with the Choeropotamidae is upheld and close relationship of the family with the Anthracotheriidae is argued to be unlikely. Choeropotamids are inferred to have had mixed frugivorous and browsing herbivorous diets. They seem to have diversified in the northern parts of Europe, some terminal taxa having originated following southward dispersal. [source] Evidence of dietary differentiation among late Paleocene,early Eocene plesiadapids (Mammalia, primates)AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2010Doug M. Boyer Abstract Plesiadapis cookei is an extinct relative of extant euarchontans (primates, dermopterans; scandentians), which lived in North America during the late Paleocene. P. cookei body mass has been estimated to be ,2.2 kg, making it large compared with other species of its genus from North America, but similar to some from Europe. In particular, size as well as dental form similarities to P. russelli have been noted. However, it is thought that P. russelli evolved from P. tricuspidens, and into Platychoerops daubrei. Dental similarities among P. cookei, P. russelli, and P. daubrei have been hypothesized to reflect a more folivorous diet than utilized by P. tricuspidens. Here we test the hypothesis that P. cookei is more dietarily specialized than P. tricuspidens by quantifying functionally significant aspects of molar, premolar, and incisor forms. Casts of M2s and P4s of P. tricuspidens, P. cookei, and P. daubrei were microCT-scanned. We measured the relief index and/or the complexity from surface reconstructions of scans. Results show that P. cookei has higher M2 relief and complexity than P. tricuspidens; P. daubrei exhibits the highest relief and complexity. Similarly, P. cookei has a more complex P4 than P. tricuspidens, whereas that of P. daubrei exhibits the highest complexity. Finally, the I1 of P. cookei resembles more the incisor of P. daubrei than that of P. tricuspidens. Because high relief and complexity of dentitions are related to fibrous plant diets in living mammals, these findings support the hypothesis that previously identified similarities among P. cookei, P. russelli and P. daubrei reflect a folivorous diet. Am J Phys Anthropol, 2010. © 2009 Wiley-Liss, Inc. [source] Body mass in cercopithecidae (Primates, Mammalia): Estimation and scaling in extinct and extant taxaAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2002Brenda R. Benefit No abstract is available for this article. [source] The Spleen of Zaedyus pichiy, (Mammalia, Dasypodidae): a Light and Electron Microscopic StudyANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 4 2003E. J. Galíndez Summary Armadillos are ancient mammals important as models for biomedical, evolutive and ecological studies, because they have adaptive and primitive morpho-physiological characteristics. In this work we study the splenic microarchitecture of the ,Patagonian Piche', Zaedyus pichiy, as an attempt to understand the relationship between the organizational plan of the organ and the particular features of this species. The organ samples were classically processed for light and electron microscopic study. The microanatomy of the organ as well as its different cell types are studied. The spleen is non-sinusoidal, with the typical arrangement for storage functions. White pulp is well defined. Red pulp is a meshwork of circulating, immunocompetent and haemopoietic cells. The general structure of the organ agrees with the semi-fossorial habit and the adaptability of the species. Comparative aspects with other armadillos or other less specialized groups are discussed. Persistence of haemopoietic spleen activity in the adult suggests the existence of specific inductive functions of the stroma. Better knowledge of spleen structure and function in ancient mammals may give important information about their phylogeny. [source] Genetic and morphological variation in a Mediterranean glacial refugium: evidence from Italian pygmy shrews, Sorex minutus (Mammalia: Soricomorpha)BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2010RODRIGO VEGA At the Last Glacial Maximum (LGM), the southern European peninsulas were important refugia for temperate species. Current genetic subdivision of species within these peninsulas may reflect past population subdivision at the LGM, as in ,refugia within refugia', and/or at other time periods. In the present study, we assess whether pygmy shrew populations from different regions within Italy are genetically and morphologically distinct. One maternally and two paternally inherited molecular markers (cytochrome b and Y-chromosome introns, respectively) were analysed using several phylogenetic methods. A geometric morphometric analysis was performed on mandibles to evaluate size and shape variability between populations. Mandible shape was also explored with a functional approach that considered the mandible as a first-order lever affecting bite force. We found genetically and morphologically distinct European, Italian, and southern Italian groups. Mandible size increased with decreasing latitude and southern Italian pygmy shrews exhibited mandibles with the strongest bite force. It is not clear whether or not the southern Italian and Italian groups of pygmy shrews occupied different refugia within the Italian peninsula at the LGM. It is likely, however, that geographic isolation earlier than the LGM on islands at the site of present-day Calabria was important in generating the distinctive southern Italian group of pygmy shrews, and also the genetic groups in other small vertebrates that we review here. Calabria is an important hotspot for genetic diversity, and is worthy of conservation attention. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100, 774,787. [source] Comparative phylogeography of four Apodemus species (Mammalia: Rodentia) in the Asian Far East: evidence of Quaternary climatic changes in their genetic structureBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2010HÉLA SAKKA The phylogeography of four Apodemus species (Apodemus agrarius, Apodemus peninsulae, Apodemus latronum, and Apodemus draco) was studied in the Far East of Asia, based on sequences of the mitochondrial DNA cytochrome b gene. The results obtained show the existence of many different genetic lineages within the studied Apodemus species, suggesting the isolation and differentiation of populations in multiple refuge areas. Higher genetic diversities in some regions such as Yunnan, Sichuan (China), and eastern Russia suggest these areas are potential refuges for these species. The existence of such complex genetic structures could be linked to the presence of many biogeographic barriers (Himalaya Mountains, Tien-shan Mountains, Altai Mountains, Tibetan Plateau, Gobi desert, Yunnan Guizhou Plateau, Dzungaria basin, and others) in these regions, which were probably reinforced during the Quaternary climate changes. These barriers also played an important role concerning the low dispersal abilities of the two studied Apodemus species adapted to forest habitats (A. latronum and A. draco) with respect to colonizing regions other than China. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100, 797,821. [source] At the foot of the shrew: manus morphology distinguishes closely-related Cryptotis goodwini and Cryptotis griseoventris (Mammalia: Soricidae) in Central AmericaBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2010NEAL WOODMAN Small-eared shrews (Mammalia, Soricidae) of the New World genus Cryptotis are distributed from eastern North America to the northern Andes of South America. One well-defined clade in this genus is the Central American Cryptotis mexicana group, whose members are set off from other species in the genus by their variably broader fore feet and more elongate and broadened fore claws. Two species in the C. mexicana group, Cryptotis goodwini Jackson and Cryptotis griseoventris Jackson, inhabit highlands in Guatemala and southern Mexico and are presumed to be sister species whose primary distinguishing feature is the larger body size of C. goodwini. To better characterize these species and confirm the identification of recently-collected specimens, we obtained digital X-ray images of the manus from large series of dried skins of both species. Measurements of the metacarpals and phalanges successfully separated most specimens of C. goodwini and C. griseoventris. These measurements also show that the fore feet of C. griseoventris from Chiapas, Mexico, are morphologically distinct from those of members of the species inhabiting Guatemala. Univariate, bivariate, and multivariate analyses indicate that fore foot characters are more conservative within species of the C. mexicana group than are cranio-mandibular characters. Patterns of evolution of fore foot characters that superficially appear to be linear gradations are actually more complex, illustrating individual evolutionary trajectories. No claim to original US government works. Journal compilation © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99, 118,134. [source] Investigating South American biogeographic history using patterns of skull shape variation on Cerdocyon thous (Mammalia: Canidae)BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2009FABIO DE A. MACHADO Patterns of geographic variation of the canid Cerdocyon thous have historically been obscured by its remarkable intraspecific morphological variability. The observed distribution is highly associated with phytophysiognomy, a feature considered highly dynamic along geological time. In the present study, we tested whether vegetation distribution during the Holocene Glacial Maximum of South America (HGM) explains the patterns of morphological variation within Cerdocyon thous. The species was divided in groups according to paleohabitats that could support their presence during the HGM, and then tested for differences in skull morphometrics. The results obtained demonstrate that the climatic changes during the HGM influenced the population structure of this species, resulting in the establishment of geographical groups with different degrees of morphological cohesion. Higher morphological cohesion found in the Northern group might be explained by the marked discontinuity between its geographical range and the rest of the species'distribution. The Eastern and Southern morphological divergence is less striking and, although this could be related to past vegetation distribution, the disappearance of those barriers leads to a population structure that could be slowly breaking down. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 98, 77,84. [source] |