In this study, I compared the species composition, species diversity, and stand structure of the Lithocarpus edulis plantation and the Castanopsis sieboldii forest in the Miura Peninsula, central Japan. The vegetation units identified using the phytosociological method were the L. edulis plantation and Ardisio-Castanopsietum sieboldii. Compared with Ardisio-Castanopsietum sieboldii, it was found that the species composition of the L. edulis plantation was characterized by the presence of L. edulis and Prunus speciosa and the absence of the many of the component species of Ardisio-Castanopsietum sieboldii (e. g., Ilex integra, Camellia japonica, and Eurya japonica). The number of species per 100 m² , the number of species of shrub layer and herb layer, the number of species of trees and lianas, a, and H' in the L. edulis plantation were significantly lower than those in the Ardisio-Castanopsietum sieboldii. The number of seed-origin and sprout-origin juveniles (0.3 m < height < 2.0 m) of L. edulis in the L. edulis plantation was significantly higher than those in the Ardisio-Castanopsietum sieboldii. Conversely, the number of sprout-origin juveniles of C. sieboldii and Quercus acuta was significantly lower in the L. edulis plantation than in the Ardisio-Castanopsietum sieboldii. My results suggest that the L. edulis plantation regenerate from the sprout-origin juveniles of L. edulis and maintain low species diversity.

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A sponge associated mysid crustacean, Heteromysis komaii Fukuoka, 2004, infecting in the gastral cavity of sponge, Callyspongia confoederata (Ridley, 1884), is reported based on the specimens from the northeastern coast of Izu-Ohshima Island, Sagami Sea, central Japan. The host sponges are distributed between 10 to 45 m in depth in our field observation. Eighty-four sponges were found in the region of about 6000 m², and H. komaii infected in the gastral cavity of 6 colonies of the sponges. In this case, 25 individuals of H. komaii composed of several stages of both sexes infected in a gastral cavity of C. confoederata. This finding is the second record of H. komaii.

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According to literature, the red swamp crayfish, Procambarus clarkii (Girard, 1852) was introduced into Kamakura, Kanagawa Prefecture, Japan in 1927, as food for the bullfrog, Rana catesbeiana, from New Orleans, Louisiana, U. S. A. Procambarus clarkii spread all over the Japanese Archipelago, though the introduction occurred only once. We examined the history of introduction of P. clarkii based on archive in the Kamakura municipal office and specimens from New Orleans present study. Furthermore, its origin, the present status at the initial introduced place, and the number of P. clarkii introduced into Japan were referred through observation of their symbionts (Annelida: Clitelia) and lineages of the initial introduction.

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We performed four types of sampling surveys using beam trawls and a sledge net during 2002-2006 in order to reveal the brachyuran fauna and its diversity at the subtidal flat area in Tokyo Bay. Species composition, k of rank-abundance relationship (Motomura's geometric series), expected number of species from Hurlbert rarefaction curve (ES(50)), logarithmic inverse of Simpson's index (log (1/D)), and Pielou's evenness index (J') were determined. Similarities of the species composition between the present and preceding studies were evaluated using Pearson's phi correlation. In this study, a total of 16,916 individuals from 41 species of 16 families were collected. The top three species, Carcinoplax vestita, Pyromaia tuberculata, Charybdis bimaculata accounted for 95% of the total samples in number. Every diversity index of this study were lower than the previous study at the same area in 1950's. Phi coefficient showed the species composition of 2002-2006 had the positive similarity to that of 1970's-1980's, but negative to 1950's. Those results suggest that the brachyuran fauna of Tokyo Bay considerably changed both quantitatively and qualitatively during 1960's probably due to environmental changes.

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Distribution of the crabs were investigated at the land and the freshwater area of Enoshima Island, Kanagawa Prefecture, central Japan from September 2009 to August 2010. Living crabs, carcasses, excuviae and their nests were confirmed at 66 localities all over the island. The number of the species of the crabs came up to nine, which were Ocypode stimpsoni, Eriocheir japonica, Chiromantes haematocheir, Chiromantes dehaani, Sesarmops intermedium, Parasesarma pictum, Cyclograpsus intermedius, Acmaeopleura parvula and Geothelphusa dehaani. It is noteworthy that living individual of Ocypode stimpsoni was recorded for the first time in this area.

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An adult male of hymenopodid mantis Acromantis japonica Westwood, 1889 was collected from Hayama-machi, the northern Miura Peninsula by the present author. This is 3rd record of adult in Kanagawa Prefecture (cf. Enju & Hamaguchi, 2005; Ohba & Miura Peninsula Insect Research Club (eds.), 2005).

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We investigated the benthic macro-invertebrate fauna at 40 sites of the Sagami River System in Kanagawa Prefecture. 403 species belonging to 142 families were recorded, and 36 species were newly recorded to Kanagawa Prefecture. 7 alien species and 16 endangered species were confirmed during this study. Numbers of Taxa, ASPT (Average Score Per Taxa) values based on Biological Monitoring Working Party (BMWP) adopted for Japan, EPT (species numbers of Ephemeroptera, Plecoptera, Trichoptera families) suggest that water quality in 40 sites were good, and much better in upstream sites. According to the result of TWINSPAN analysis and relationship with the some environmental dates, Sagami River Systems can be divided into 4 types of river morphology

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Aetobatus flagellum (Bloch et Schneider, 1801) and Mobula diabolus (Shaw, 1804) (Rajiformes: Myliobatidae) were first recorded from Sagami Bay on the basis of single specimen each. The specimen of the former is a female of 337.5mm in disk width fished off Enoshima on 28 May, 2010, and the latter one is a female of 1860.0 mm in disk width fished off Komekami on 26 July, 2010. Additionally, two specimens of Evoxymetopon taeniatus Gill, 1863 (Perciformes: Trichiuridae) without a scientific record from the bay were collected from Kawana (607.2mm SL, 11 March, 2009) and Tateyama Bay (1638.0 mm SL, 90m depth, 14 March, 2010). Their descriptions, figures, and notes on the distribution were given.

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The amount of flow in main stream-A is about 60 to 70 times more than the other branches, but the number of collected Oncorhynchus masou masou and Cottus pollux were less than the other branches. In the main stream, during 20 % period of the experiment, heavy turbidity was observed. In order to protect O. masou masou and C. pollux in stream-A, we need to stop suspended solids from flowing into the stream and create the artificial spawning ground for increasing fishes and so on, immediately.

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Ichthyofauna of Sagami Bay has been researched bay landing fishes of Misaki Fish Market, and 567 species has been recorded since 1986. In the paper, seven species are additionally recorded.

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Fish fauna in the coasts of Yokahama,Kawasaki and Nakanose areas in Tokyo Bay were researched and over 300 species has hitherto been recorded from the areas. In the recent survey 17 species are newly recorded from the areas from November 2004 to October 2010. Especially, the following 9 species are the first records from inner part of Tokyo Bay: Syngnathoidest biaculeatus, Onigocia spinosa, Apogon notatus, Sparus sarba, Scarus ghobban, Parapercis snyderi, Scartella emarginata, Istigobius campbelli, and Scatophagus argus.

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We are studying of fish fauna in the southwestern coast of the Miura Peninsula since 1988. 452 species of fishes were previously recorded. 18 species are newly added in the present study from November 2004 to October 2010. Eviota prasina, Oxyurichthys sp., Ptereleotris zebra, P. heteroptera and Scatophagus argus are the first record on the basis of specimens from Sagami Bay.

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