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Burrow system characteristics of seven small mammal species (Mammalia: Insectivora; Rodentia; Carnivora)  [cached]
G.N. Bronner
Koedoe : African Protected Area Conservation and Science , 1992, DOI: 10.4102/koedoe.v35i1.396
Abstract: Burrow system characteristics of seven small mammal species (Mammalia: Insectivora; Rodentia; Carnivora)
Giant bunodont Lutrinae from the Mio-Pliocene of Kenya and Uganda  [cached]
Morales, J.,Pickford, M.
Estudios Geologicos , 2005, DOI: 10.3989/egeol.05613-666
Abstract: Three new species of bunodont otters are described from the Mio-Pliocene of East Africa. They are provisionally attributed to the genus Sivaonyx Pilgrim, 1931. The species described are Sivaonyx soriae, nov. sp. and Sivaonyx senutae nov. sp. from the Latest Miocene Lukeino Formation (Kenya) and Sivaonyx kamuhangirei nov. sp. from the Pliocene of Kazinga and Warwire (Uganda). Additional material of the species Sivaonyx ekecaman (Werdelin, 2003) is described from Sagatia, Mabaget Formation (Kenya). The systematics of the new tribe Enhydriodontini are discussed and we report the presence of evolutionary tendencies in the bunodont African otters: increase in body size, modification of the carnassial teeth. In particular in the P4/ the protocone becomes well separated from the paracone, at the same time that an anterior valley develops. Se describen tres nuevas especies de nutrias bunodontas del Mio-plioceno de Africa oriental. Provisionalmente se adscriben al género Sivaonyx Pilgrim 1931. Las especies descritas son Sivaonyx soriae nov. sp y Sivaonyx senutae nov. sp. del Mioceno final de la formación Lukeino (Kenia), y Sivaonyx kamuhangirei nov. sp del Plioceno de Kazinga y Warwire (Uganda). También se describen nuevos fósiles de Sagatia, formación Magabet (Kenia) atribuibles a la especie Sivaonyx ekecaman (Werdelin, 2003). Se discute la sistemática de la nueva tribu Enhydriotini y se se ala la presencia de dos tendencias evolutivas en las nutrias bunodontas africanas: incremento de talla y modificación de las carniceras. Especialmente del P4/ en el que el protocono se va separando del paracono, al mismo tiempo que se desarrolla un valle en posición anterior.
Mio-Pliocene Faunal Exchanges and African Biogeography: The Record of Fossil Bovids  [PDF]
Faysal Bibi
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0016688
Abstract: The development of the Ethiopian biogeographic realm since the late Miocene is here explored with the presentation and review of fossil evidence from eastern Africa. Prostrepsiceros cf. vinayaki and an unknown species of possible caprin affinity are described from the hominid-bearing Asa Koma and Kuseralee Members (~5.7 and ~5.2 Ma) of the Middle Awash, Ethiopia. The Middle Awash Prostrepsiceros cf. vinayaki constitutes the first record of this taxon from Africa, previously known from the Siwaliks and Arabia. The possible caprin joins a number of isolated records of caprin or caprin-like taxa recorded, but poorly understood, from the late Neogene of Africa. The identification of these two taxa from the Middle Awash prompts an overdue review of fossil bovids from the sub-Saharan African record that demonstrate Eurasian affinities, including the reduncin Kobus porrecticornis, and species of Tragoportax. The fossil bovid record provides evidence for greater biological continuity between Africa and Eurasia in the late Miocene and earliest Pliocene than is found later in time. In contrast, the early Pliocene (after 5 Ma) saw the loss of any significant proportions of Eurasian-related taxa, and the continental dominance of African-endemic taxa and lineages, a pattern that continues today.
STUDY OF GENOTOXICITY OF ENVIRONMENTAL CHEMICAL POLLUTION ON TWO SPECIES OF GENUS APODEMUS (RODENTIA MAMMALIA)
H. Pour-Jafari,D.D. Farhud,A.R. Mesdaghinia
Iranian Journal of Public Health , 1998,
Abstract: In present work, genotoxicological effects of chemical pollution of an industrial region, on species of genus Apodemus (Rodentia, Mammalia), were studied. The two species were A.flavicolis and A.agrarius. In this study, chromosomal aberrations of bone marrow cells were analysed and were compared according to sex and different species in polluted and unpolluted (control) areas. Results showed that frequencies of chromosomal aberrations, including breaks, between two groups were statistically significant (P<0.005); and also sensitivity of two sexes and two species against chemical pollutant, were not significant.
Current status of Myoxids (Mammalia: Rodentia) in Calabria (Southern Italy)
Mara Cagnin,Gaetano Aloise
Hystrix : the Italian Journal of Mammalogy , 1995, DOI: 10.4404/hystrix-6.1-2-4027
Abstract: Four species of Myoxids are presently known to live in the southern region of the Italian peninsula: Eliomys quercinus, Dryomys nitedula, Myoxus glis, Muscardinus avellanarius. The only paleontological evidence, dating from the Würm period, refers to E. quercinus, M. avellanarius and M. glis, which were found in caves of the Northern Thyrrenian Coast. The historical data concerning the Calabrian Myoxids, do not include the presence of Dryomys nitedula which was recorded for the first time in the Aspromonte Massif only in 1964 (von Lehmann, 1964). The actual geographical distribution of D. nitedula in Southern Italy seems to include the Calabrian and Basilicata mountains. The ecological distribution of D. nitedula seems to be tied to the presence of beech woods from 1300 m to 1800 m above sea level. Present knowledge concerning Calabrian Glirids is very scanty and fragmentary since no specific studies have been carried out. Most available data refer to Muscardinus avellanarius, a species frequently found in bird of prey pellets (mainly froin Tyto alba) from sea level to 1300 m a.s.l., both in the sclerophyll and in the decidous biomes. By contrast, few data dealing with Eliomys quercinus exist probably due to a fragmented distribution within this region. Myoxus glis seems to be frequent and continous, in areas ranging from sea level to wooded mountains. Riassunto Stato delle conoscenze sui Mioxidi (Rodentia, Mammalia) in Calabria - In Calabria, la regione più meridionale della penisola italiana, sono presenti quattro specie di Mioxidi: Eliomys quercinus, Dryomys nitedula, Myoxus glis e Muscardinus avellanarius. Gli scarsi dati paleontologici risalenti a1 Würm, di caverne della costa Tirrenica settentrionale segnalano la presenza di E. quercinus, M. glis e M. avellanarius. Anche i dati storici, non riportano la presenza di D. nitedula, rinvenuto in Aspromonte solo nel 1964 (von Lehmann, 1964). La distribuzione geografica attuale del Driomio in Italia meridionale comprende le montagne calabresi e della Basilicata in cui sembra legato alle faggete a quote superiori ai 1300 metri slm. Le conoscenze attuali sui Mioxidi in Calabria sono piuttosto scarse e frammentarie poiché non sono stati svolti studi specifici. La maggior parte dei dati disponibili riguardano il Moscardino, specie che si rinviene di frequente nei rigetti di rapaci (in particolare di Tyto alba) dal livello del mare fino a 1300 metri slm, sia nel bioma delle sclerofille che in quello delle caducifoglie. Scarse invece sono le informazioni sul Quercino che ha probabilmente una distribuz
Antilopinae (Bovidae, Mammalia) from the Lower Pliocene of Teruel Basin (Spain)  [cached]
Alcalá, L.,Morales, J.
Estudios Geologicos , 2006, DOI: 10.3989/egeol.0662159
Abstract: Two genera of Antilopinae are identified in the Lower Pliocene localities of the Teruel Basin: Hispanodorcas and Gazella. Hispanodorcas is represented at La Calera by a new species, Hispanodorcas heintzi nov. sp., which is characterised by the development of a strong anterior keel in the horn cores. Gazella is represented in La Calera and Villalba Alta localities by a new species, Gazella soriae nov. sp., which is defined by its small size and weak transversal compression of the horn cores. A species smaller than Gazella soriae, Gazella baturra nov. sp. is identified at La Gloria 4. En los yacimientos del Plioceno inferior de la Fosa de Teruel se han identificado dos géneros de Antilopinae: Hispanodorcas y Gazella. Hispanodorcas está representado en La Calera por una nueva especie: Hispanodorcas heintzi nov. sp., que está caracterizada por el desarrollo de una fuerte quilla anterior en sus núcleos óseos de cuerno. Gazella está representada en La Calera y Villalba Alta por una nueva especie, Gazella soriae nov. sp., que está definida por su peque a talla y escasa compresión transversal de los núcleos óseos de cuerno. Una especie de menor talla todavía que Gazella soriae se clasifica como Gazella baturra nov. sp. en La Gloria 4.
Late Cenozoic History of the Genus Micromys (Mammalia, Rodentia) in Central Europe  [PDF]
Ivan Horá?ek, Markéta Knitlová, Jan Wagner, László Kordos, Adam Nadachowski
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0062498
Abstract: Molecular phylogeography suggests that Micromys minutus, the sole extant species of the genus, colonized its extensive range quite recently, during the Late Pleistocene-Holocene period. Rich Pliocene and Pleistocene fossil records both from Europe and China suggest rather continuous and gradual in situ phenotype rearrangements from the Pliocene to the Recent periods. To elucidate the discrepancy we reexamined a considerable part of the European fossil record of the genus (14 sites from MN15 to Q3, 0.4–4.2 Ma, including the type series of M. preaminutus from MN15 Csarnóta 2), analyzed them with the aid of detailed morphometric comparisons, and concluded that: (a) The European Pliocene form, M. praeminutus, differs significantly from the extant species; (b) it exhibits a broad phenotypic variation covering the presumptive diagnostic characters of MN16 M. caesaris; (c) despite having smaller dimensions, the Early and Middle Pleistocene forms (MN17-Q3, 2.6–0.4 Ma) seem to be closer to M. praeminutus than to the extant species; (d) the extinction of M. praeminutus during Q3 and the re-occupation of its niche by the recent expansion of M. minutus from E-European – C Asiatic sources (suggested by phylogeographic hypotheses) cannot be excluded. Discussing interpretations of the phylogenetic past of the genus we emphasize the distinct history of the West Palearctic clade (Late Miocene-Early Pleistocene) terminating with M. praeminutus and the East Asiatic clade (chalceus, tedfordi, minutus), and the possible identity of the Western clade with the Late Miocene genus Parapodemus.
A Late Miocene Dolichotinae (Mammalia, Rodentia, Caviidae) from Uruguay, with comments about the relationships of some related fossil species  [cached]
Martín Ubilla,Andrés Rinderknecht
Mastozoolog?-a neotropical , 2003,
Abstract: Un Dolichotinae (Mammalia, Rodentia, Caviidae) del Mioceno tardío de Uruguay, con comentario sobre las afinidades de especies fósiles relacionadas. Se describe el registro más antiguo de Dolichotinae para el Uruguay proveniente de depósitos del sur-oeste y asignables al Mioceno tardío y se incluye dentro del género Prodolichotis . Su tama o es intermedio entre las especies Pediolagus salinicola y Dolichotis patagonum y similar a Prodolichotis lacunosa. El material consiste en un cráneo incompleto con el diastema mas largo que la serie P4-M3; foramen nasolacrimal no apreciable en vista lateral; borde anterior de la fosa mesopterigoidea ubicado entre los prismas del M2; hendidura posterior interna del M3 con bordes divergentes formando un ángulo menor de 90o. Esta configuración del M3 compartida por el clado Dolichotinae-Caviinae sugiere que la condición de poseer bordes paralelos en este molar que presentan los actuales Dolichotinae podría ser una característica derivada y no primitiva, y la configuración existente en el M3 de los cavinos primitiva. Teniendo en cuenta algunas características morfológicas de Prodolichotis pridiana foramen nasolacrimal visible en vista lateral, ancho interorbitario menor que el ancho de la caja craneana, hendidura posterior interna del M3 con bordes divergentes concordamos con opiniones previas, en que esta especie debe incluirse en Caviinae y no en Dolichotinae. Se discuten evidencias para incluir al género Orthomyctera dentro de la subfamilia Caviinae: ancho interorbitario marcadamente menor que el de la caja craneana; MACNlargo de la serie P4-M3 menor que el largo del diastema; foramen nasolacrimal expuesto lateralmente en el maxilar y M3 similar al de los cavinos. La presencia de un dolichotino en el Mioceno tardío del Uruguay sugiere ambientes terrestres abiertos y probablemente áridos o semiáridos.
Clay Mineralogy and Diagenesis of Shales: A Case Study from the Mio-Pliocene Tipam and Dupi Tila Shales of Bandarban Anticline, Bandarban Hill District, Bangladesh  [PDF]
A.K.M. Masud Alam,Shucheng Xie,Sifatul Q. Chowdhury
Journal of Applied Sciences , 2009,
Abstract: A detailed clay mineralogical investigation has been conducted on shale samples from the Mio-Pliocene Tipam Sandstone and Dupi Tila Formations of the Bandarban Anticline, Bandarban Hill District, Bangladesh. The whole shale and the <2.0 μm fractions of the samples were treated for thin section petrography and XRD analysis. The predominant clay minerals identified are kaolinite, illite, mixed-layer illite/smectite, chlorite and muscovite. Mixed-layer illite/smectite forms a major group and there are indications that the diagenesis has taken place involving gradual loss of illite/smectite from younger to older rocks. The gradual decrease of the illite/smectite proportion in the random illite/smectite clay is reflected by a gradual decrease in the 17 peak intensity which is possibly interpreted as a decrease in the percentages of smectite layers in the illite/smectite clay due to the diagenetic transformation of smectite to illite. This may be a source of additional silica to the interbedded sandstones for the generation of little quartz overgrowth cementation. It is expected that a small volume of water derived from the smectite diagenesis should have been available and migrated from smectite interlayers to the pore water system, contributing to the generation of overpressure encountered in the subsurface of Bandarban Structure. Moreover, kaolinite clay mineral displaying decreasing tendency in older rocks is amongst other diagenetic changes recorded in studied shale.
Karyotypes of two rare rodents, Hapalomys delacouri and Typhlomys cinereus (Mammalia, Rodentia), from Vietnam  [cached]
Alexei Abramov,Vladimir Aniskin,Viatcheslav Rozhnov
ZooKeys , 2012, DOI: 10.3897/zookeys.164.1785
Abstract: Karyotypes of Hapalomys delacouri (Rodentia, Muridae) and Typhlomys cinereus (Rodentia, Platacanthomyidae) from Vietnam are described for the first time. The diploid karyotype of H. delacouri is 38 (NFa=48), consisting of six pairs of bi-armed and 12 pairs of acrocentric autosomes decreasing in size; plus a large metacentric X chromosome and Y chromosome, also metacentric, that is equal in size to the largest pair of acrocentric autosomes. The newly described karyotype differs significantly from that reported for H. delacouri from northern Thailand. The latter record very likely represents a different species of Hapalomys, possibly the taxon H. pasquieri described from north-central Laos. The diploid karyotype of Typhlomys cinereus is 38 (NF=48), consisting of five pairs of meta- to submetacentric and 14 pairs of acrocentric chromosomes varying in size from large to small; sex chromosomes were not defined.
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