著者
Kawada Shin-ichiro Harada Masashi Obara Yoshitaka Kobayashi Shuji Koyasu Kazuhiro Oda Sen-ichi
出版者
社団法人日本動物学会
雑誌
Zoological science (ISSN:02890003)
巻号頁・発行日
vol.18, no.7, pp.1003-1010, 2001-09-20
被引用文献数
14 23

A detailed analysis was done on the karyotypes of four species of mole in the genera Euroscaptor and Mogera using a G-banding technique. All four species examined had a chromosome number of 2n = 36, as reported previously. Euroscaptor mizura and M. wogura from Aichi Prefecture had almost the same chromosome constitution and G-banding patterns. These common karyotypes were considered to be equivalent to the hypothetical ancestral karyotype of Mogera, since two distinct genera derived from an ancestor share G-banding homologies. According to this hypothesis, the karyotype of M. imaizumii might have been derived from the ancestral karyotype through pericentric inversion in one pair of acrocentrics, chromosome 11. Two geographically isolated populations of M. tokudae had different karyotypes : the Echigo population had the same karyotype as M. imaizumii, whereas the Sado population had a derivative karyotype that was able to be explained by pericentric inversions in three pairs of acrocentrics, remaining chromosome 11 as subtelocentric. Mogera wogura from South Korea differed considerably in terms of chromosome constitution from the Japanese population of M. wogura. However, we deduced that pericentric and paracentric inversions in four pairs of acrocentrics would explain the karyotype differences between the Japanese and Korean populations. Furthermore, from the morphology of chromosome 11, we can conclude that the Korean mole was derived from primitive M. wogura through four inversions, quite separately from the lineage of M. imaizumii and M. tokudae. Thus, inversion rearrangements appear to have played a major role in the chromosomal evolution of Japanese talpine moles.
著者
Kawada Shin-ichiro Koyasu Kazuhiro Zholnerovskaya Elena I. ODA Sen-ichi
出版者
日本哺乳類学会
雑誌
Mammal study (ISSN:13434152)
巻号頁・発行日
vol.27, no.2, pp.107-111, 2002-12-01
被引用文献数
2 2

The upper dental formula of the Russian desman Desmana moschata (Linnaeus, 1758) (Insectivora, Talpidae) is considered based on the position of the premaxillary suture (sutura incisiva). From the lateral aspect, this suture extends to the second tooth in the tooth row. From the ventral aspect, the suture connects the common alveolus fossa of the second and third teeth in front of the second tooth on the labial edge and behind it on the lingual edge; consequently, the third tooth in the upper row appears to be derived from the maxilla. Therefore, the upper tooth formula of D. moschata may differ from the traditional fundamental dental formula of eutherian mammals (I3, C1, P4, M3), and consist of two incisors, one canine, five premolars, and three molars (I2, C1, P5, M3). This hypothetical view, however, assumes two changes, a tooth deletion in the incisor row and an addition in the premolar row. The significance of the premaxillary suture and possible pitfalls in using it to define dental formulae are discussed.
著者
Kawada Shin-ichiro Shinohara Akio Yasuda Masatoshi ODA Sen-ichi LIAT Lim Boo
出版者
日本哺乳類学会
雑誌
Mammal study = The Continuation of the Journal of the Mammalogical Society of Japan (ISSN:13434152)
巻号頁・発行日
vol.30, no.2, pp.109-115, 2005-12-01
被引用文献数
4 5

We report the first karyological description of a southeast Asian mole, the Malaysian mole (<i>Euroscaptor micrura malayana</i>). The karyotype of the Malaysian mole includes 36 chromosomes, which consist of 18 biarmed and 16 acrocentric autosomes and the sex pair. The sex chromosomes are a small meta-submetacentric X chromosome and a minute dot-like Y chromosome, although the latter is somewhat larger than that of some talpid allies. Autosomal complements include one pair of NOR-bearing chromosomes. A comparative G-banding analysis with the Japanese congener <i>E. mizura</i> showed that these two species share high G-banding homology, and their differences on two pairs of chromosomes are explained by a single reciprocal translocation. The karyological similarity of these distant geographic species is discussed in a systematic and evolutionary context, based on comparisons to other species distributed between them.<br>