Epipogium roseum, the near threatened (NT) species in the Red Lists of Japanʼ s Ministry of Environment, was found on the understory of Lithocarpus edulis plantation in Mt. Ohgusu, Miura Peninsula, central Japan. L. edulis plantation and Castanopsis sieboldii forest were divided into 1 plantation, 1 association and 2 under units as follows: (I) L. edulis plantation; (Ia) E. roseum under unit; (Ib) Reineckea carnea under unit; (II) Ardisio-Castanopsietum sieboldii. The density of E. roseum was 14.0-24.0 individuals per 100m² in the E. roseum under unit. The average scape height of E. roseum was 10.6-12.2cm in the E. roseum under unit. Result of PCA analysis demonstrated that the site conditions varied between habitats and non-habitats of E. roseum. In the E. roseum under unit, the thickness of litter layer, coverage of litter layer, and soil moisture showed a higher tendency than those in the R. carnea under unit and Ardisio-Castanopsietum sieboldii. In conclusion, the abundant plant litter and abundant or excessive soil moisture will be required to maintain the habitats of E. roseum.

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Green mussel Perna viridis Linnaeus, 1758 is a tropical originated sessile bivalve. It had been introduced to Japanese waters in no later than 1967. The first occurrence of this mussel in Tokyo Bay was reported in 1985. It had spread quickly since then and is distributed widely now. The thermal condition for the overwintering of this mussel was investigated at the artificial seashore facilities in Yokohama Port of Tokyo Bay from 2010 to 2011. The survival rates of the mussel during the winter were 0.116 in 2010 and 0.387 in 2011 respectively. The lowest monthly mean water temperature of each year were 12.1°C (February, 2010) and 11.7°C (February, 2011), and the lowest mean temperature of the trisected period of the month were calculated as 11.4°C (Middle January, 2010) and as 11.3°C (Middle January, 2011). The durations of the lower temperature were estimated from recording times of each lower temperature level. It was suggested that the amount of durations of under 12℃ , 11℃ and 10℃ temperature levels were shorter than those of the extinction accrued year. The warm waters which are originated from Kuroshio current or freshwaters are considered to have influences for the overwintering of this mussel.

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The nereidid polychaete Leonnates persicus Wesenberg-Lund originally described from the Percian Gulf is currently known from the Indian Ocean and Western Pacific Oceans. In Japanese waters, it was recorded from the Ariake Sound and Kagoshima, Kyushu, Tokushima, Hyogo, and Mikawa Bay. Here we report a new record of this species from shallow water locations of Haneda, Tokyo Bay.

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Distribution of the crabs were investigated at the land and brackishwater area of the Sagamigawa river, Kanagawa Prefecture, central Japan from November 2006 to August 2011. Living crabs, carcasses, exuviae and their nests were confirmed at 109 localities all over the study area. The number of the species of the crabs came up to 17, which were Portunus pelagicus, Portunidae sp., Deiratonotus cristatum, Scopimera globasa, Pachygrapsus crassipes, Ptychognathus ishii, Eriocheir japonica, Hemigrapsus sanguineus, Hemigrapsus penicillatus, Gaetice depressus, Chiromantes haematocheir, Chiromantes dehaani, Parasesarma pictum, Sesarma bidens, Chasmagnathus convexus, Helice tridens and Plagusia dentipes. They are noteworthly that living individuals of Ptychognathus ishii was recorded for the first time at Kanagawa Prefecture and living individuals and their nests of Scopimera globasa was recorded for the first time in ten and several years in this area.

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We investigated the benthic macro-invertebrate fauna at 40 sites of the Sakawagawa River system of Kanagawa Prefecture, and 391 species belonging to 138 families were recorded. Among them, 6 species were newly recorded in Kanagawa Prefecture. 6 alien species and 11 endangered species were found during this investigation. Numbers of taxa, ASPT (Average Score Per Taxa) values based on Biological Monitoring Working Party (BMWP) adapted for Japan, and EPT (species numbers of the orders, Ephemeroptera, Plecoptera, Trichoptera) indicates that water quality in 40 sites was generally good, and much better in upstream sites. According to the result of TWINSPAN analysis and relationship with the some environmental dates, the Sakawagawa River system can principally be divided into 4 types of river morphology as the case in the Sagamigawa River system.

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Remarkable insects found on coastal areas of the Miura Peninsula of southeastern Kanagawa Prefecture are recorded mostly with biological notes. They are 32 families and 72 species including some first records from Kanagawa Prefecture.

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ln order to clarify the distribution of Lefua echigonia Jordan and Richardson, 1907 (Cypriniformes: Cobitidae: Nemacheilinae) in Atsugi City，Kanagawa Prefecture, Japan, a field survey was carried out at a total of 122 stations on 8 river systems from June 2009 to October 2011. As a result, the species was found from the following 36 stations: 10 in Oginogawa River System; 4 in Mayumigawa River System; 1 in Koayugawa River System; 8 in Onzogawa River System; 10 in Tamagawa River System; 3 in Hinatagawa River System. Among these stations, the species occurred in high density at the source of river in secondary nature called as "yato." On the other hand, the density was low in an upper reach and a main stream in a river. The environment of "yato" was characterized by having spring water, slow flow, rich water plants and/or dead leaves on sandy-muddy bottom, and low density of Procambarus clarkii, where located at altitudes of 40 to 90 m. The density was much higher than that of "yato" in a biotope reconstructed artificially. Therefore, it is essential to manage their habitat for conservation of this species. Coloration of 163 live specimens were analyzed by a digital image taken in a field. The pattem of coloration was divided into 4 types on the basis of distribution of black spots on body. The ratio of occurrence of each type was different every river system. This suggests thatitis necessary to make a plan for conservation every river system.

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The distributions of fresh-water goby, the genus Rhinogobius were investigated at 181 stations in 25 rivers of Kanagawa Prefecture. As the result, 7 species (Rhinogobius giurinus, R. sp. CB, R. fluviatilis (=R. sp. LD), R. sp. CO, R. brunneus (=R. sp. DA), R. kurodai (=R. sp. OR), R. flumineus were collected from 100 stations. Each species occurred at high frequency in order of R. sp. CB, R. fluviatilis, R. kurodai, R. giurinus, R. sp. CO, R. flumineus. By contraries, R. brunneus were extremely rare, and it was recorded only from three rivers in the Miura Peninsula .

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Occurrences of oarfishes, Regalecus russelii (Cuvier, 1816) (Lampriformes: Regalecidae) in Sagami Bay were reviewed. There are seven certain records of this species from the bay on the basis of specimen or image. Their size of body ranged from 10-30 cm to 4.9 m in total length, and the captured season was from January to February, July and September to October. The specimen of 1817 mm in total length collected at Komekami on January 19, 2011 was very fresh and good condition, although the posterior portion of tail suffered a loss like many other examples. We first confirmed that the dorsal fin is composed of three parts, i.e. five elongate spines connected with fin membrane, one free spine with flaps, and subsequent soft rays. The counts and measurements are given in detail.

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The fish fauna of the Sakawa River System was investigated at the 40 sites in the mainstream and its 16 tributaries. Total of 33 species 11 families of freshwater fishes were recorded, and consisted of 21 genuine, 11 diadromous and 1 peripheral species. The widest distributed species was Phoxinus lagowskii steindachneri, Oncorhynchus masou masou, Cottus pollux, Tribolodon hakonensis, Zacco platypus，Pseudogobio esocinus esocinus and Cobitis biwae. The lower mainstream and the tributaries such as the Kanase River, Senryou River and Kari River have a rich fauna.

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In our study on fish fauna of Sagami Bay since 1986, 574 species have been recorded on the basis of specimens landed on Misaki Fish Market from Sagami Bay. In this paper, fourteen species are additionally recorded. Among them, Scomberoides tol, Pterocaesio digramma, Evoxymetopon poeyi and Arothron manilensis are new to the bay.

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