Time filter

Source Type

Higashimurayama-shi, Japan

Sugamori Y.,Osaka Museum of Natural History | Sugamori Y.,Osaka City University

The Ajima Formation of the Ultra-Tamba Terrane has been regarded as Mesozoic fore-arc sediments and is mainly distributed in the western part of the Sasayama area, southwest Japan. The formation consists mainly of clastic rocks with a small amount of basalt and hydrothermal chert, and tectonically overlies the Middle Triassic Kamitaki Formation. The Ajima Formation is previously considered as Mesozoic or Late Jurassic, the newly discovered radiolarian fauna from the siliceous mudstone intercalated with sandstone and siltstone of the formation, however, corresponds to the upper part of the Neoalbaillella ornithoformis assemblage zone and the Albaillella levis abundance zone (early Changhsingian). Although the Ajima Formation and Ultra-Tamba Terrane in the Hokusetsu area are regarded as Late Jurassic fore-arc sediments (Inagawa Group of Ishiga, 1990a), unconformably overlying the Permian subduction-related accretionary complex, this study suggests that these strata tectonically overly the Triassic and Jurassic subduction-related accretionary complex of the Tamba Terrane or Middle Triassic formation, as Permian strata. Then the radiolarian fauna from the Ajima Formation implies that the highly abundant fauna of A. levis thrived not only in the central Panthalassa but also in the western margin of the Panthalassa. © 2011 Elsevier Ltd and Nanjing Institute of Geology and Palaeontology, CAS. Source

Five species of the family Cyproideidae (Crustacea: Amphipoda) are described from shallow sea in Japan. Cyproidea li-odactyla Hirayama, 1978 was collected from Kanagawa and Shizuoka Prefectures and Ariake Sea. Morphological char-acter of the antenna 1 in these specimens is different from the original description. Examining the paratypes of C. liodactyla, the shape of the antenna 1 in the holotype is revealed to be abnormal. Cyproidea okinawensis sp. nov. was collected from Okinawa Island. Its morphological characters resemble C. liodactyla and C. robusta Ren, 2006; however, this new species is different from the former in the smaller eyes, the narrower coxa 5 and the coloration, and from the latter in the ovoid telson. Metacyproidea gen. nov. is established with M. makie sp. nov. from Hachijo Island in Tokyo Prefec-ture as its type species. This new genus resembles Cyproidea, especially in the peduncular article 2 of antenna 1 with a distinct distal tooth and the posterodorsal end of urosomites with a strong projection. However, Metacyproidea can be dis-tinguished from Cyproidea by the coalesced urosomites 2-3 and the antenna 1 with a 10-16-articulated flagellum. Mool-apheonoides acutifalcatus Kobayashi & Ishimaru, 2005 and Terepeltopes dolichorhunia Hirayama, 1983 were also collected from Wakayama and Fukui Prefectures and Kanagawa, Shizuoka and Yamaguchi Prefectures, respectively. A key to species of the family Cyproideidae in Japan is provided. Copyright © 2016 Magnolia Press. Source

Takasuka K.,Ehime University | Matsumoto R.,Osaka Museum of Natural History
Journal of Ethology

Unique host enticing behaviour has been observed for the first time in Zatypota albicoxa (Walker), which parasitizes the house spider, Parasteatoda tepidariorum (Koch), which weaves irregular, three-dimensional webs. One female wasp lay on her dorsum on the floor and grasped one of the vertical gumfoot threads with her legs (reclining-style). The wasp picked the thread with her legs, feigning a captured and struggling prey. Although this behaviour seems to be a variety of the ambush style, it is quite similar to that of a wandering and captured wingless insect, and it seems an adaptation to the host being hidden in a complex web. As the wasp touched the gumfoot directly, this suggests the possession of behavioural or morphological mechanisms for avoiding entrapment by the sticky masses on the web. Diversity in mode of attack correlates with the fact that the spider constructs webs of various forms in a variety of situations. Digital video images relating to the article are available at http://www.momo-p.com/showdetail-e.php?movieid=momo100416za03a, http://www.momo-p.com/showdetail-e.php?movieid=momo100416za03a, http://www.momo-p.com/showdetail-e.php?movieid=momo100415za01a, http://www.momo-p.com/showdetail-e.php?movieid=momo100415za01a, http://www.momo-p.com/showdetail-e.php?movieid=momo100416za01a, http://www.momo-p.com/showdetail-e.php?movieid=momo100416za01a, and http://www.momo-p.com/showdetail-e.php?movieid=momo100416za02a, http://www.momo-p.com/showdetail-e.php?movieid=momo100416za02a. © 2011 Japan Ethological Society and Springer. Source

The Mutual Climatic Range method of Paleotemperature reconstruction is well suited to Japan, because the meteorological stations are densely located, and the modern distributions of beetles are well studied. Many of the cold adapted species which were in the Japanese lowlands during glacial periods still survive at higher elevations on the Japanese Archipelago, in high mountain refuges. A new way of drawing convex polygons as species envelopes is proposed here, make the method more accurate and objective. A test analysis using four beetle species from a stratum in the Nojiri-ko site, Nagano Prefecture is presented. The test shows a decline of temperatures, the first example of MCR from East Asia. The result agrees with the previous estimation based on modern range overlaps and on reconstructions based on vegetation. © 2013 Elsevier Ltd and INQUA. Source

Three new species of the Eriopisa group (Crustacea: Amphipoda: Eriopisidae) are described from coastal areas in Japan. Paraflagitopisa gen. nov. is established with P. excavata sp. nov. as its type species. This new genus is characterized by (1) entire lateral cephalic lobe, (2) unfused flagellum of antenna 2, (3) 3-articulated mandibular palp, (4) carpus of gna-thopod 1 longer than propodus, (5) transverse palm of gnathopod 1, and (6) slender outer ramus of uropod 3 with long second article, and can be distinguished from the closely related genus, Flagitopisa, by the article 2 of mandibular palp longer than article 3, the undilated bases of pereopods 3-4, and the slender inner ramus of uropod 3. Psammogammarus lobatus sp. nov. is characterized by (1) male gnathopod 2 with excavated palm, (2) posterodistally projected bases of pe-reopods 5-7, (3) quadrate posteroventral corner of pleonal epimeron 3, (4) short inner ramus of uropod 3, and (5) article 2 of uropod 3 outer ramus longer than article 1. Victoriopisa wadai sp. nov. has the following characters: (1) eyes absent, (2) peduncle of antenna 1 not heavily setose, (3) accessory flagellum with 1-2 articles, (4) flagellum of antenna 2 com-posed of 2 long and 3 short articles, (5) gnathopod 2 in both sexes with excavated palm, (6) merus of pereopod 7 moder-ately expanded, and (7) ventral margin of pleonite 2 slightly setose. Key to species of the Eriopisa group in Japan is provided. Copyright © 2015 Magnolia Press. Source

Discover hidden collaborations