Hakone-Tokyo tephra consists of air fall pumice deposits named Hk-TP and pumice flow deposits. The lowest unit of the Hk-TP is usually thicker on the Miura Peninsula and its distribution axis may be more towards the east. On the contrary, the upper one of two coarse-grained pumice fall units of Hk-TP is relatively thinner and its distribution range may be more northward. The total thickness of Hk-TP may be thicker than previous estimates. Massive pumice flow deposits, named Hk-T(pfl), are newly found at two outcrops in the Miura Peninsula, suggestive of a wider distribution of the pumice flow.

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From December 27 to 28, 2014, using the deep sea survey system DEEP TOW on the Research Vessel “Yokosuka” YK 14-22 cruise (KO-OHO-O cruise IV), Japan Agency for Marine-Earth Science and Technology (JAMSTEC), we conducted submarine surveys at the Sagami Knoll in the Sagami Bay in twice (YKDT # 160, # 161), and at the branch of the Iro Submarine Canyon in the southern Izu Peninsula offshore (YKDT # 162). In the Sagami Knoll, the survey was made along the steep slope of the south side of the Knoll and the dive started from the middle terrace and then progressed in the direction of rising along the slope. The slope consists mainly of mudstone, but three to four layers of conglomerate were found therein. Ten rock samples were collected by the dredgers during the dive (YKDT # 161). In the branch of the Iro Submarine Canyon, diving started from the downstream side, focusing on the stricture part of the canyon midstream, passing through the narrowing toward upstream, and finally rose up the ridge-like topography of the narrowing. Outcrops were widely observed near the stricture, where were found the conglomeratic body in the lower and the layered and massive complex in the upper. The valley floor of the stricture part was sandy and/or pebbly and ripple marks were widely observed on the sea floor. Those ripple marks show the flow direction mostly from the downstream side to the upstream side. It is not a normal flow along the canyon, and infers some flow due to bottom current. On the basis of the rock samples collected in this submarine survey, we examined the compositions of volcanic rocks and confirm that they are andesite to dacite.

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We attempted to count type materials and taxa of vascular plant collections in Kanagawa Prefectural Museum of Natural History, in order to make them useful for future researches, and analyzed their configurations based on specimen attributes such as localities of prefectures, collection years, and collectors. As a result, 183 type materials including 46 holotypes are deposited in the museum. We calculated the ratio of the taxa in the museum to those recorded in all Japan and prefectures, only by the number without considering the compositions types. The museum holds vascular plant specimens of 89.4 % for the whole country of Japan, and of 95.4 % for Kanagawa Prefecture with the largest collection. The composition of prefectural collections with a large number of specimens is due to the contribution by Mr. Tatsuyuki Ohba, Mr. Miyoshi Furuse, and Mr. Hideo Takahashi. The number of specimens is also larger in Shizuoka and Chiba prefectures, resulting from other collector and specific flora investigations.

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Sixteen tropical and two temperate fish species whose distributions are biased to the south of the Japanese Archipelago were collected from the rivers and coastal areas of Sagami Bay and adjacent waters. Oligolepis stomias was newly reported from the Kanto area representing the northernmost record for the species. Eleotris fusca, Ophieleotris sp. 1, Taenioides sp. B, Oxyurichthys lonchotus, Callogobius tanegasimae, Bathygobius hongkongensis, Drombus sp., Favonigobius reichei and Scatophagus argus were recorded for the first time from Chiba Prefecture and these are the easternmost specimen-based records for the species. The occurrence of Plectorhinchus gibbosus in Zushi represents a new specimen-based record from Kanagawa Prefecture. Lutjanus argentimaculatus, Lutjanus rivulatus, Lutjanus fulvus, Kuhlia marginata, Oligolepis acutipennis, Redigobius bikolanus and Bathygobius peterophilus were also noted. These specimens and research of other specimens, pictures and literature surveys show that, in Sagami Bay and adjacent waters, the numbers of stations where each fish species were recorded has increased in recent years. In addition, the total numbers of recorded or settling species are increasing over time in not only the collecting area but also in other areas north of Kyushu along the Kuroshio Current. These results indicate northward range extensions along the Kuroshio Current for these warm water fishes, and can be explained by a rising trend in sea surface temperature caused by global warming.

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Euurobracon yokahamae (Dalla Torre, 1898) is interpreted as an endangered species (Level II) in the Red List of Kanagawa Prefecture. However, over the last ten years, eyewitness accounts and collecting records of the species have been increasing, especially on chestnut trees and surrounding coppices. Its hosts have long been considered to be larvae and pupa of Batocera lineolata and larvae of Massicus radddei. In this study, it is clarified that E. yokahamae infested the pupa of M. raddei, based on such remains as head capsules and normally molted outer peels of the hosts.

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The invasive alien mantis Hierodula sp. has already established in Japan, but introduction routes of the species have not been elucidated so far. We newly found the egg cases which are considered to be of this kind of species, from commercially imported bamboo brooms. We also confirmed that they were able to hatch normally and that their morphological and color features are consistent with already known larvae of the species. If bamboo brooms play a main role in relation to the introduction, it can be reasonably explained what the species has been confirmed in various places at the same time. Their colonization pattern looks different from that normally seen in other alien species.

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Two ichneumonid parasitoids of the genera Aptesis Förster, 1850, and Javra Cameron, 1903, associated with a serious forest pest of sawfly, Fagineura crenativora (Tenthredinidae, Nematinae), are studied. A new species, A. flavitrochanterus sp. nov. is described. This species resembles A. melana Li & Sheng, 2013, and A. opaca (Cushman, 1937), but the females can be distinguished by the following combination of character states: hind trochanter and trochantellus largely white to yellow (black to brown in A. melana and A. opaca); first metasomal tergite 1.4–1.85 times as long as maximum width (1.3 times in A. melana); body length 3.5–5.5 mm (8.5–10.0 mm in A. opaca); ovipositor sheath longer than first metasomal tergite and 0.9–1.0 times as long as hind tibia (shorter than first metasomal tergite in A. opaca and 0.8 times as long as hind tibia in A. melana). A Korean species, J. coreensis (Uchida, 1930) is newly recorded from Japan with the first host record. Keys to Japanese species of both genera are also available

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Polytribax penetrator (Smith, 1874) (Hymenoptera, Ichneumonidae, Cryptinae) has been known as a parasitoid of Aculeata wasps (Hymenoptera, Eumenidae and Pomplidae) (Masuda, 1941). While we record Neozephyrus japonicus (Murray, 1875) (Lepidoptera, Lycaenidae) as the host of P. penetrator for the first time. This record shows the following biological information: 1) this species is solitary parasitoid; 2) adult wasp of this species emerged from the pupa of the butterfly; 3) the host range of this species is generalist type; 4) a membrane-like wall is present between anterior and posterior parts of host pupa. This is also the second record of Polytribax species of parasitism to Lycaenidae in the world.

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The habitat of the Japanese weasel was surveyed by capture in the lower Karigawa River, Kanagawa Prefecture. Three weasel males were captured in 16 days. Based on the surveyed are, the population density of the weasel males was estimated to be 0.14 and 0.31 per hectare in the riverbed area of the lower Karigawa river.

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