The taxonomic status and species limits of the South African-endemic rodent species Otomys saundersiae were revised using G-banding karyotypic analysis, assessment of pelage colour and craniodental traits, multivariate analysis of eight cranial distance measurements, and geometric morphometric analysis of 11 landmarks of the dorsal image of the skull. In the Western Cape, the recognized subspecies Otomys saundersiae karoensis differed in karyotype from sympatrically-occurring populations of O. irroratus (cytotype "C") in having six (as opposed to four) pairs of biarmed chromosome pairs and in the absence of pair number 14. Discriminant analysis of linear craniometric variables in positively identified (karyotyped) samples of Otomys irroratus and Otomys s. karoensis separated the two species without any overlap, as did pelage colour and certain qualitative cranial characters such as nasal angle; such clear-cut differences however were not apparent between unkaryotyped samples of O. s. saundersiae and O. irroratus from the Eastern Cape. Centroid size (from geometric morphometric analysis of cranial landmarks) was significantly correlated with both non-affine and affine components of skull shape, indicating strong allometric effects. Both cranial shape and size differed significantly between Western Cape O. s. karoensis and O. irroratus ; size, but not shape, varied significantly between Eastern Cape O. s. saundersiae and O. irroratus . Within both currently recognized species, significant geographical differences in cranial shape were detected between eastern and western Cape populations occupying distinct ecological biomes. Problems with defining species limits in this complex case were discussed with reference to available data and alternative species concepts.
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Requires Authentication UnlicensedSpecies with fuzzy borders: the taxonomic status and species limits of Saunders' vlei rat, Otomys saundersiae Roberts, 1929 (Rodentia, Muridae, Otomyini)LicensedJuly 6, 2007
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Requires Authentication UnlicensedTaxonomic status of Micronycteris homezi (Chiroptera, Phyllostomidae)LicensedJuly 6, 2007
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Requires Authentication UnlicensedSmall mammals of Maulino forest remnants, a vanishing ecosystem of south-central ChileLicensedJuly 6, 2007
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Requires Authentication UnlicensedSmall mammal communities of tropical forest habitats in Mudumalai Wildlife Sanctuary, southern IndiaLicensedJuly 6, 2007
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Requires Authentication UnlicensedMensural discrimination of Myotis (Chiroptera, Vespertilionidae) in the southeastern United StatesLicensedJuly 6, 2007
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Requires Authentication UnlicensedBats of the Potaro Plateau region, western GuyanaLicensedJuly 6, 2007
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Requires Authentication UnlicensedActivity rhythms, movements and patterns of sett use by badgers, Meles meles, in a Mediterranean woodlandLicensedJuly 6, 2007
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Requires Authentication UnlicensedCamera-trap study of ocelot and other secretive mammals in the northern PantanalLicensedJuly 6, 2007
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Requires Authentication UnlicensedDefense behavior and nest architecture of Metachirus nudicaudatus Desmarest, 1817 (Marsupialia, Didelphidae)LicensedJuly 6, 2007
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Requires Authentication UnlicensedNew data on chromosomes from murid Rodents of Benin - The karyotype of Myomys derooiLicensedJuly 6, 2007
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Requires Authentication UnlicensedGlyphonycteris daviesi (Hill, 1964), a rare Central American and Amazonian bat recorded for Eastern Brazilian Atlantic Forest (Chiroptera, Phyllostomidae)LicensedJuly 6, 2007
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Requires Authentication UnlicensedCache pilferage in red-rumped agoutis (Dasyprocta leporina) (Rodentia)LicensedJuly 6, 2007
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Requires Authentication UnlicensedWinter distribution of European pine marten (Martes martes) scats in a protected area of Galicia, SpainLicensedJuly 6, 2007
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Requires Authentication UnlicensedPossible evidence of a thermoregulatory response to increasing above ground ambient temperature in the water vole (Arvicola terrestris L.)LicensedJuly 6, 2007
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Requires Authentication UnlicensedA documented 20th century record of Javan Rhinoceros Rhinoceros sondaicus from CambodiaLicensedJuly 6, 2007
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Requires Authentication UnlicensedRégime alimentaire du rat-taupe géant, Cryptomys mechowi, sur le plateau de Bateke, République Démocratique du CongoLicensedJuly 6, 2007