Wyniki wyszukiwania - Biblioteka Nauki

1

Dental anomalies in the Japanese mole Mogera wogura from northeast China and the Primorsky region of Russia

100%

Asahara M. , Kryukov A. , Motokawa M.

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nr 1

EN

Dental anomalies in the Japanese mole, Mogera wogura Temminck, 1842, from northeast China and the Primorsky region of Russia were examined based on 241 specimens. The most frequent dental anomaly was oligodonty, i.e., missing P2 (18 cases) or P3 (one case). Supernumerary teeth were observed in three cases, two of which were characterized by abnormal shapes. Morphological abnormalities in teeth (six cases) and an asymmetrically curved rostrum (one case) were also observed. Dental anomalies were found at higher frequencies in populations near the northern range limit of the species. This was not caused by size effects. We suggest that the high incidence of dental anomalies was the result of genetic drift, which increases in marginal populations. Considering the nature of subterranean mammals, our results suggest that the high frequency of dental anomalies in a marginal population could have initiated the evolution of dental formulae if parapatric or peripatric speciation occurs in such populations.

2

Taxonomic study of the water shrews Chimarrogale himalayica and C. platycephala

75%

Motokawa M. , Harada M. , Apin L. , Yasuma S. , Yuan S. L. , Lin L. K.

Acta Theriologica

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2006

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tom 51

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nr 2

215-223

EN

We investigated karyotypes, mitochondrial cytochromeb gene sequences, and cranial morphometries of the water shrewsChimarrogale himalayica (Gray, 1842) andC. platycephala (Temminck, 1842) (Insectivora, Soricidae). Karyotypes ofC. himalayica from Taiwan andC. platycephala are 2n=52 and FNa=100. Autosomes consisted of 21 large-to-small metacentric or submetacentric pairs, and 4 medium-to-small subtelocentric pairs. The X and Y chromosomes were medium submetacentric and small acrocentric, respectively. The karyotypes ofC. himalayica andC. platycephala were very similar. Secondary constrictions were observed in the largest metacentric pair in both species. In the 930 base-pairs of the cytochromeb gene,C. himalayica from Taiwan andC. platycephala diverged with 9.46% sequence difference; each species diverged fromC. phaeura with more than 14% sequence difference. The two speciesC. himalayica andC. platycephala were well distinguished by morphometric characters, but three subspecies ofC. himalayica were not clearly separated. We suggest thatC. platycephala be treated as a valid species and separated fromC. himalayica in Taiwan.

3

A new species of the genus Murina (Chiroptera: Vespertilionidae) from the Central Highlands of Vietnam with a review of the subfamily Murininae in Vietnam

63%

Son N. T. , Csorba G. , Tu V. T. , Thong V. D. , Wu Y. , Harada M. , Oshida T. , Endo H. , Motokawa M.

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nr 2

EN

The subfamily Murininae has high species diversity in Vietnam, but taxonomic studies are limited. In this paper, we describe a new species of the genus Murina based on a specimen collected from Ngoc Linh Nature Reserve, Kon Tum Province in the Central Highlands of Vietnam. It is a medium-sized species with ‘suilla-type’ dentition. A taxonomic review of Murininae from Vietnam was also conducted based on combined morphological, DNA, and karyological characteristics. Molecular phylogenetic analyses based on the mitochondrial cytochrome c oxidase subunit (COI) gene supported the subfamily Murininae, while the genus Murina proved to be paraphyletic in relation to the genera Harpiocephalus and Harpiola. Fourteen species of the genus Murina, one species of Harpiocephalus, and one species of Harpiola are recognized from Vietnam. Murina tiensa is regarded as a junior synonym of M. harrisoni; strong sexual dimorphism was observed in M. harrisoni. Relations between forearm length and total length of skull showed different trends among species and sexes. Karyotypes of Murina huttoni, M. cyclotis, M. lorelieae, M. beelzebub, M. feae, and Harpiola isodon were 2n = 44, FN = 50, while that of Harpiocephalus harpia was 2n = 44, FN = 52.

4

Description of a new species of Myotis (Vespertilionidae) from Vietnam

63%

Son N. T. , Gorfol T. , Francis C. M. , Motokawa M. , Estok P. , Endo H. , Thong V. D. , Dang N. X. , Oshida T. , Csorba G.

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nr 2

EN

During the examination of a series of specimens, formerly referred to Myotis montivagus, recently collected in Vietnam and Lao PDR, we found that they differ in several important ways from any species formerly included in M. montivagus. We describe them as a new species characterised by a relatively long forearm, moderately long ears, flat cranial profile and wide anteorbital bridge. Based on characters classically used to separate the ‘subgenera’ of Myotis the new species shows affinities to both the nominate subgenus ‘Myotis’ and ‘Selysius’. Our morphological investigations support recent phylogenetic analyses showing that the former ‘subgenera’ of Myotis are in fact paraphyletic groups, even within Southeast Asia. Nevertheless, many of the external and craniodental features formerly used to separate these subgenera provide a practical means of grouping species. Using these characters we provide an identification key to identify the new species, as well as other currently recognized medium and large sized, small-footed Myotis species from the Indomalayan Region.