159 resultados para first offender
Resumo:
The parasitic isopod genus Gigantione is first recorded from China. Four species are reported infesting xanthid and goneplacid crabs, three are new to science, and one is a new record from China. Gigantione ishigakiensis Shiino, 1941, infesting Liagore rubromaculata (De Haan); G. hainanensis sp. nov., infesting Atergatis floridus (L.) and Atergatis sp., which differs from other recorded species in the shape of its barbula, first oostegite and subrectangular maxilliped; G. rhombos sp. nov., infesting Heteroplax dentata Stimpson, Eucrate alcocki Serene and Eucrate sp., its female distinguished from other species of Gigantione by having a prominent rhombic projection on the barbula; and G. tau sp. nov., infesting Carcinoplax longimanus (De Haan), the female of which differs from other species mainly by its T-shaped pigmentation on the head. Four brachyuran crabs are first reported as hosts of bopyrids. A list of all brachyuran species so far recorded as bopyrid hosts in China is provided.
Resumo:
This paper reports the occurrence of a marine brachyuran crab species Eucrate alcocki SerSne, in SerSne et al., 1973, of the family Euryplacidae Stimpson, 1871, for first time from India, based on a male specimen from Parangipettai fish landing centre in Bay of Bengal, Southeast Coast of India. Although morphologically corresponding with what is currently defined as E. alcocki, the color pattern of the carapace of the present specimen is rather different from that of the Chinese material-only the anterior fifth of the carapace is marked with scattered red spots, the rest of the surface is yellowish, with four unusually shaped red blotches which almost look like Sanskrit characters.
Resumo:
This paper reports for the first time a species of polychaetous family Paraonidae, Paraonella platybranchia (Hartman, 1961), a rare species found previously only in the coast near the boundary between the United States and Mexico, and it was recently discovered in the samples collected in 1982 from Chinese side of the Yellow Sea. This is the first record of the species in China as well as in the Northwest Pacific.
Resumo:
Six species belonging to two families of Hemichordata have previously been recorded in Chinese waters. This paper records the discovery and description of a new species of the genus Glandiceps found in Jiaozhou Bay, Qingdao, Shandong Province, named Glandiceps qingdaoensis. The new species has a long proboscis with dorsal and ventral grooves, a stomochord with a long vermiform process, a proboscis cavity with a dorsal median, right and left glomeruli, right and left glomeruli very large and encircling the stomochord, a proboscis skeleton in the cavity extends into the median posterior of the collar, a well-developed dorsal ventral muscular septum in the proboscis cavity dividing the cavity completely into two separate parts. The collar cord is without giant nerve roots. The trunk with four distinct regions that can be recognized externally: branchial-genital region, genital region, hepatic region, and intestinal region. The dorsal pharynx is large and the gill pores are small. The tongue bars are encircled by vesicles, and the first gonad commences at the level of the second or third gill slit.
Resumo:
Sponges (phylum Porifera) had been considered as an enigmatic phylum, prior to the analysis of their genetic repertoire/tool kit. Already with the isolation of the first adhesion molecule, galectin, it became clear that the sequences of sponge cell surface receptors and of molecules forming the intracellular signal transduction pathways triggered by them, share high similarity with those identified in other metazoan phyla. These studies demonstrated that all metazoan phyla, including Porifera, originate from one common ancestor, the Urmetazoa. The sponges evolved prior to the Ediacaran-Cambrian boundary (542 million years ago [myr]) during two major "snowball earth events", the Sturtian glaciation (710 to 680 myr) and the Varanger-Marinoan ice ages (605 to 585 myr). During this period the ocean was richer in silica due to the silicate weathering. The oldest sponge fossils (Hexactinellida) have been described from Australia, China and Mongolia and are thought to have existed coeval with the diverse Ediacara fauna. Only little younger are the fossils discovered in the Sansha section in Hunan (Early Cambrian; China). It has been proposed that only the sponges possessed the genetic repertoire to cope with the adverse conditions, e.g. temperature-protection molecules or proteins protecting them against ultraviolet radiation. The skeletal elements of the Hexactinellida (model organisms Monorhaphis chuni and Monorhaphis intermedia or Hyalonema sieboldi) and Demospongiae (models Suberites domuncula and Geodia cydonium), the spicules, are formed enzymatically by the anabolic enzyme silicatein and the catabolic enzyme silicase. Both, the spicules of Hexactinellida and of Demospongiae, comprise a central axial canal and an axial filament which harbors the silicatein. After intracellular formation of the first lamella around the channel and the subsequent extracellular apposition of further lamellae the spicules are completed in a net formed of collagen fibers. The data summarized here substantiate that with the finding of silicatein a new aera in the field of bio/inorganic chemistry started. For the first time strategies could be formulated and experimentally proven that allow the formation/synthesis of inorganic structures by organic molecules. These findings are not only of importance for the further understanding of basic pathways in the body plan formation of sponges but also of eminent importance for applied/commercial processes in a sustainable use of biomolecules for novel bio/inorganic materials.
Resumo:
A new species, Axianassa sinica, from the Beibu Gulf (Gulf of Tonkin), northern South China Sea, is described and illustrated. The new species is readily distinguished from A. australis Rodrigues & Shimizu, 1992, by its acute rostrum, merus of pereopod 1 with a tooth distally on lower margin and an elongated telson.
Resumo:
The low-cost and commercially available (-)-ephedrine hydrochloride was firstly employed in the [RuCl2(1)-cymene)](2)-catalyzed asymmetric transfer hydrogenation of prochiral ketones in water. The reaction could be performed in the open air at rt, affording excellent yields (up to 99%) and good enantioselectivities (up to 83% ee). It provided a further step toward the discovery of simplified catalyst systems for eventual availability. (c) 2005 Published by Elsevier Ltd.