The Miyata Formation distributed in Miura Peninsula is subdivided into 4 units based on lithology and unconformity. They consist of light yellowish brown tuffaceous sandstone (A), dark gray brownish tuffaceous sandy gravel (B), alternation of dark brown sandy gravel and light gray brownish mudstone (D), and pale reddish brown tuffaceous fi ne-grained sandstone (C), in ascending order. Their stratigraphic relationships are angular unconformities, respectively. Their valley-shaped erosion surfaces are considered to be due to global sea-level change related to glacial and interglacial periods. They are similar to ones known in the Sagami Group in the southern part of the Tama hills. Those precise geologic ages are still unknown, and then radiometric age dating was attempted using zircon minerals of the Funakubo Tuff (Fn), intercalated in the uppermost C unit of the Miyata Formation. As a result, their FT and U-Pb ages by Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) are 0.41 Ma.

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Recently, one specimen each of Chlorophthalmus nigromarginatus Kamohara, 1953 (Aulopiformes: Chlorophthalmidae), Aulopus formosanus Lee and Chao, 1994 (Aulopiformes: Aulopidae) and Foetorepus masudai Nakabo, 1987 (Perciformes: Callionymidae) were collected from Suruga Bay, Japan. These specimens represent the fi rst record of each species from the bay and the northernmost record for the species. It is suggested that the Kuroshio Current impacts on their dispersion like it does for many reef and shore fi shes; their distribution is continuous in southern Japan along the path of the current.

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Two new lentic, relatively small-sized species of the gobiidid fish genus Rhinogobius, R. tyoni and R. telma, are described based on specimens from temperate regions of Japan. Rhinogobius tyoni (14 specimens, 25.7–40.0 mm SL) is distinguished from all congeneric species by the following combination of features: predorsal area with small cycloid scales; 8–17 predorsal scales; 20–23 pectoral-fin rays; 28–35 longitudinal scales; 10+16=26 vertebrae; a low first dorsal fin in males, not extending posteriorly to origin of second dorsal fin when adpressed; third spine of first dorsal fin longest; posterior oculoscapular canal usually absent; preopercular canal usually present; anteriorpart of first dorsal fin with no dark large circle or quadrangle markings; caudal fin with some dark vertical lines in males, some dark vertical lines or rows of dots in females. Rhinogobius telma (14 specimens, 28.7–39.5 mm SL) differs from all congeneric species by the following combination of features: predorsal area with small cycloid scales; 3–15 predorsal scales; 10+16=26 vertebrae; a low first dorsal fin in males, not extending posteriorly to origin of second dorsal fin when adpressed; third spine of first dorsal fin longest; lateral and ventral sides of belly with ctenoid and small cycloid scales, respectively; posterior oculoscapular canal and preopercular canal absent; first dorsal fin with a single longitudinal row of vertically-elongate dark markings; caudal fin with some vertical rows of dark dots in both sexes.

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The world’s heaviest bony fish, Mola alexandrini (Tetraodontiformes: Molidae) has a long history of being confused with Mola mola. It was recently discovered that a specimen of Mola alexandrini was mixed in with specimens of the genus Mola stored in the Kanagawa Prefectural Museum of Natural History. This specimen was caught by set net off Manazuru, Kanagawa Prefecture (35˚10’N, 139˚08’E), Japan, on 28 October 1977. Via the Enoshima Aquarium (before refurbishment), it is now exhibited as a mounted specimen in the Kanagawa Prefectural Museum of Natural History. This specimen represents the fifth whole body specimen of this species from Japan and an additional record from Kanagawa Prefecture. Factors that made it difficult to identify this specimen were suggested as “deformation of the mounting process” and “morphological abnormality of clavus”.

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Specimens of nine crab species that are mainly distributed in the south of the Japanese archipelago (Cycloachelous granulatus, Ilyograpsus nodulosus, Macrophthalmus banzai, Metopograpsus thukuhar, Parapyxidognathus deianira, Ptychognathus capillidigitatus, Ptychognathus ishii, Scylla serrata, Varuna litterata) and two rare crab species (Camptandrium sexdentatum, Sestrostoma toriumii) were collected from rivers flowing into the Sagami Bay and adjacent waters to improve their records for this region. For some species, the specimens included ovigerous females or were collected in autumn and the following spring, suggesting overwintering and range extension in this region, possibly due to increasing water temperatures as a result of global warming.

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Amynthas japonicus (Horst, 1883) was one of three native earthworms first described from Japan in Dr P.F.B. von Siebold’s collection from around 1820s (Edo period). While the other two species are relatively well known and their current distributions mapped, the species of concern has not been found since. An expedition organized to collect earthworms from the probable Nagasaki type-locality failed to find this worm. This, coupled with review of surveys by other workers, shows that this species has not been recorded for nearly 200 years and is either particularly rare or, more likely, extinct. Its current IUCN Redlisting as Data Deficient but “Possibly extinct” should now be reclassified as “Extinct”. This is the first earthworm and second invertebrate extinction from Japan. An updated checklist of known Japanese native earthworms is appended.

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The first native earthworm formally described from Australasia, Tokea orthostichon (Schmarda, 1861), also has the distinction of now being classed extinct. Lingering doubts about its identity have been largely dismissed due to inspection of primary type (Vienna) and of other museum specimens (Hamburg, London) that have been erroneously claimed as such.

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The ecology and life history of Euurobracon yokahamae (Dalla Torre, 1898) are being clarified rapidly in recent years. However, its egg-laying has not been observed because the behavior is done using thin tunnels made by cerambycid larvae of Massicus raddei. For the direct observation of oviposition behavior of E. yokahamae, we tried to use an industrial endoscope. As a result, we firstly succeeded to confirm the position of the ovipositor at laying to the host, and were able to record it in the photographs. In addition, four examples of parasitized pupas (and pre-pupa) of Massicus raddei by E. yokahamae were newly confirmed in the chestnut tree. Subsequent continuous observation under the rearing conditions almost revealed the life history of E. yokahamae including larvae, pupas, and emergence.

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Invasive alien mantis Hierodula sp. was firstly reported in Fukui Prefecture in 2010, and recorded from Kanagawa Prefecture in 2015. This species is regarded as originated from China. In this paper, detailed distribution survey results are shown, and additional records of the species are described from Odawara-City and Yamakita-Town in western part of the prefecture. In those areas, this species is considered to be in the early stage of invasion, and coexists with the native ones. Egg capsule sheaths of the alien species are also found in commercially available Chinese bamboo brooms, and the habit of this species to fl y toward light was fi rst observed in Gifu Prefecture.

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Taxonomic and zoogeographical notes of 21 genera of Japanese Cryptinae are reported. Five new species, Giraudia japonica sp. nov., Ischnus splendens sp. nov., Nematopodius (Nematopodius) montanus sp. nov., Xoridesopus amamiensis sp. nov. and X. tokarensis sp. nov. are newly described. Giraudia japonica sp. nov. resembles G. gyratoria (Thunberg, 1822) in the yellow scutellum and the normal shaped wings, but can be distinguished by the following combination of character states: postpetiole covered with fi ne and distinct sculptures; base of antenna black: hind trochanter and trochantellus blackish brown; metasomal tergites more or less darkened. Ischnus splendens sp. nov. apparently resembles I. bimaculatus Jonathan, 2006 (male unknown) from India in the body with many yellow markings and the frons with a median carina and a few longitudinal striations, but it can be easily distinguished by the following combination of character states: MSL 1.0–1.1 times as long as MSL hind coxa with two yellow markings, one at dorsally and other at anteroventrally. Nematopodius (N.) montanus sp. nov. resembles N. formosus Gravenhorst, 1829, but it can be distinguished by the nervellus intercepted anterior to midpoint (intercepted posterior to midpoint in N. formosus) and the antenna already without a white band (usually with a small white band). Xoridesopus amamiensis sp. nov. apparently resembles X. nigritibia Gupta & Gupta, 1983, from Indonesia, but it can be distinguished by the following combination of character states: epomia weakly present; hind femur reddish brown; T3 densely punctate. X. tokarensis sp. nov. apparently resembles X. schuleri (Dalla Torre, 1902) from India, Burma and Indonesia, but it can be distinguished by the following combination of character states: hind coxa largely black; scutellum densely punctate. Two species, Apsilops scotinus (Tosquinet, 1903) and Nematopodius (Nematopodius) debilis (Ratzeburg, 1852) are newly recorded from Japan. Three synonyms are newly recognized, i.e., Dihelus niger Gupta & Gupta, 1978 = D. hylaevorus (Momoi, 1966) (syn. nov.), Gerdius iriomotensis Kusigemati, 1986 = Eurycryptus sakaguchii (Uchida, 1932) (syn. nov.) and Torbda parallela Momoi, 1970 = T. sauteri Uchida, 1932 (syn. nov.). Two new combinations of the generic status of Cryptus ohshimensis Uchida, 1930, and Torbda takachihoensis Momoi, 1966, are proposed, i.e., the former is transferred to Hedycryptus and the latter is to Pterocryptus (comb. nov.). Some new distribution records in Japanese Cryptinae are also reported.

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