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Article type: Appendix
2006 Volume 20 Pages
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[in Japanese]
Article type: Article
2006 Volume 20 Pages
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[in Japanese]
Article type: Article
2006 Volume 20 Pages
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[in Japanese]
Article type: Article
2006 Volume 20 Pages
2-3
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[in Japanese]
Article type: Article
2006 Volume 20 Pages
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[in Japanese]
Article type: Article
2006 Volume 20 Pages
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[in Japanese]
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2006 Volume 20 Pages
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[in Japanese]
Article type: Article
2006 Volume 20 Pages
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Utsugi Jinbo, Takayuki Suzuki
Article type: Article
2006 Volume 20 Pages
6-14
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This article reviews our Internet project activities to establish on-line databases of Japanese moths. Though many large on-line databases of moths are available in the world, only a few resources were available in Japan until our projects began. Our projects consist of the following three parts. "An Identification Guide of Japanese Moths Compiled by Everyone" (http://www.jpmoths.org/) is a huge database which stores 12,000 photographs of 3,200 species. "List MJ: A tentative checklist of Japanese moths" (http://listmj.mothprog.com/) is an up-to-date checklist of Japanese moths. "Gaml" (http://www.mothprog.com/moth/gaml) is a mailing-list for exchanging various information concerning taxonomic, ecological and faunastic studies on moths. One of these "Everyone's Handmade Identification Guide…" is a characteristic project. Most of photographs in this database are taken and identified by anonymous collaborators including some researchers. When a contributor posts a moth image on the bulletin board at the website, someone identifies the image and then the webmaster registers the identified image in the database. These projects provide a communication base for all those interested in moths. They are also useful for researchers since the posted images sometimes include remarkable information for them. These projects will contribute to international projects of biodiversity databases. Further information gathering and improving of accuracy of identification are issues in the future.
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Yoshiki Masuda
Article type: Article
2006 Volume 20 Pages
15-22
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All species of freshwater sponges belong to the suborder Spongillina (Phylum Porifera) and are classified into seven families. Some families (such as Spongillidae comprising about 150 species) are geographically widespread, while others (such as Lubomirskiidae) are endemic to small areas. Spicules exsist in a variety of forms and are most important in the identification and classification of species and higher taxa. Other important key characters for identification are size, form and structure of gemmules, the gemmule coat, and micropyle. Most freshwater sponges produce gemmules, which are resistant bodies and asexual propagules. In Japan, the timing of gemmule production varies among species. Some species are hatched from gemmules in early spring and produce gemmules in early summer when water temperatures have not reached the maxima. Green color of freshwater sponge bodies is caused by the presence of algal symbionts. The algal symbionts are classified into two major groups based on the presence or absence of pyrenoid. In Spongilla lacustris, transfer of symbionts from parents to the next generation has been observed in both sexual and asexual reproduction. The classification of symbionts in several sponge species is currently under investigation using culture and molecular biological methods. Whether host specificity exists in these symbiotic algae is also under investigation. All Japanese species belong to the family Spongillidae. The Japanese species have been classified into 25 species in 11 genera. Recently, Heterorotula multidentata and Trochospongilla pennsylvanica have conspicuously increased in their geographical range in Japan, although they were not recorded before World War II. They may be exotic species introduced by human activity.
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Akio Tanikawa
Article type: Article
2006 Volume 20 Pages
23-25
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About 130 years has passed since L. Koch (1878) published the first paper on Japanese spiders. Today there are still many undescribed species in Japan. Based on papers published in the journal of the Arachnological Society of Japan during the last five years, three professional and six amateur researchers are now actively studying the taxonomy of Japanese spiders. Most of their publications are descriptive studies, e.g. description of new species, revision of a genus or a family. Phylogenetic analyses using morphological or molecular data have been published for many countries, but not for Japan. It is becoming increasingly urgent to foster young spider taxonomists. The traditional approach in taxonomy seems to be arbitrary and therefore not attractive for young researchers. Japanese leading taxonomists should adopt modern methods such as phylogenetic analyses in order to attract young successors.
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Hirokazu Ozawa
Article type: Article
2006 Volume 20 Pages
26-40
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This paper overviews water temperature and salinity ranges for living relict species of cryophilic ostracods (Crustacea: Ostracoda) in and around the Japan Sea (=Sea of Japan). Fourteen representatives of cryophilic species belonging to the families Hemicytheridae, Cytheruridae and Eucytheridae are used for geographical analysis. These results provide new information on the ecology (living water temperature and salinity) of the cryophilic ostracod fauna from Japan and their survival through the Pleistocene environmental fluctuations. By the summer temperature and salinity habitat requirements, these species could be divided into three groups: (a) Japan/open sea-inner bay (0-20℃, 30-34‰) species group; (b) Japan-Alaska/open sea (around 5℃, 31-34‰) species group; (c) Japan/open sea (0-20℃, around 34‰) species group. The winter temperature and salinity of areas inhabited by these three species groups falls in a single range of 0-5℃ and 30-34‰. The ability of all these species to tolerate a winter low temperature of less than 5℃ is considered critical for their survival. Based on their geographical distribution of modern and fossil records, these species are interpreted to have survived the cyclic environmental changes between glacial and interglacial periods in the Pleistocene by expansion or contraction of their geographical ranges. Their wide temperature and salinity tolerance is considered to be the most advantageous factor for survival through the Pleistocene environmental fluctuations in the Japan Sea, linked with the glacio-eustatic sea-level changes.
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Shin-ichiro Kawada
Article type: Article
2006 Volume 20 Pages
41-50
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The taxonomy of Japanese moles, genus Mogera, has been confused since the early 1990s, because of the poorly defined type locality of M. wogura and morphological variability within the genus. Genetic research in recent decades has clarified the taxonomic problems of Japanese moles. This paper uses Japanese moles to discuss the importance of karyological study in mammal species recognition. Chromosomal rearrangements are considered likely to have an important role in species diversification of Japanese moles, resulting from postmating isolation mechanisms induced by abnormal meiosis in heterozygotic hybrids. It is well known that recombination leads to gametes with an unbalanced complement of chromosomal segments in inversion or reciprocal translocation heterozygotes. In the case of Japanese moles, four species of Japanese moles, M. etigo, M. imaizumii, M. tokudae and M. wogura, each have a distinct karyotype and/or morphological traits, and are thus considered to be full species endemic to Honshu, Shikoku and Kyushu.
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Article type: Appendix
2006 Volume 20 Pages
51-52
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Article type: Bibliography
2006 Volume 20 Pages
53-54
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Article type: Bibliography
2006 Volume 20 Pages
54-55
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2006 Volume 20 Pages
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2006 Volume 20 Pages
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Article type: Appendix
2006 Volume 20 Pages
60-61
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Article type: Appendix
2006 Volume 20 Pages
62-64
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Article type: Appendix
2006 Volume 20 Pages
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Article type: Cover
2006 Volume 20 Pages
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