A new genus and species of shrimp(Crustacea:Axiidea:Axiidae)from the Caroline Ridge,Northwest Pacific

A new genus and species of axiid shrimp,Carolinaxius kexuae gen.et sp.nov.is described and illustrated based on a single specimen collected from an unnamed seamount in the Caroline Ridge,Northwest Pacific.Although both chelipeds are mis sing,the specimen can be distinguished from other axiid genera by a combination of characteristics:narrowly triangular ro strum;median carina and lateral gastric carina each with one prominent tooth;submedian gastric carinae converging po steriorly,with teeth;cornea weakly pigmented,eyestalk with acute distome sial tooth on dorsal surface;male pleopod 1 two-articled;pleopod 2 with appendix interna and appendix masculina;pleopods 3-5 with appendix interna.The molecular phylogeny suggests the new genus is most closely related to another recently described genus living inside hexactinellid sponges on seamounts in the Indian Ocean,Montanaxius Dworschak,2016.However,it differs from Montanaxius in the shape of the rostrum,the arrangement of teeth on the carapace,and the shape of the eyestalk.Besides,the significant molecular differences support the two belonging to different genera.

New species of the giant deep-sea isopod genus Bathynomus(Crustacea,Isopoda,Cirolanidae)from Hainan Island,South China Sea

Several specimens of the giant deep-sea isopod genus Bathynomus were collected by a deep-sea lander at a depth of 898 m near Hainan Island in the northern South China Sea.After careful examination,this material and the specimens collected from the Gulf of Aden,north-western Indian Ocean,previously reported as Bathynomus sp.,were identified to be the same as a new species to the genus.Bathynomus jamesi sp.nov.can be distinguished from the congeners by:the distal margin of pleotelson with 11 or 13 short straight spines and central spine not bifid;uropodal endopod and exopod with distolateral corner slightly pronounced;clypeus with lateral margins concave;and antennal flagellum extending when extended posteriorly reaches the pereonite 3.In addition,Bathynomus jamesi sp.nov.is also supported by molecular analyses based on mitochondrial COI and 16S rRNA gene sequences.The distribution range of the new species includes the western Pacific and north-western Indian Ocean.

Report of epibenthic macrofauna found from Haima cold seeps and adjacent deep-sea habitats,South China Sea

This work reports on a preliminary taxonomic study of epibenthic macroinvertebrates collected or observed by underwater video at the Haima cold seeps and in adjacent deep-sea habitats,including a mud volcano feld and Ganquan Plateau,during an expedition in the South China Sea by the Chinese-manned submersible Shenhai Yongshi in May 2018.A total of 41 species belonging to 6 phyla were identifed,among which 34 species were collected from the Haima cold seeps.Mollusks and crustaceans that are specialized in reducing habitats were predominant in biotopes of the Haima cold seeps,whereas sponges and cold-water corals and their commensals were prominent in communities of the mud volcano feld and the slopes of Ganquan Plateau.The distribution and faunal composition of each taxonomic group are discussed.

Biodiversity variability of macrobenthic in the Yellow Sea and East China Sea between 2001 and 2011

In this study, we compared the biodiversity and ecological status of macrobenthos between 2001 and 2011 in terms of species composition, dominant species, abundance, biomass, diversity, and secondary productivity of macrobenthos in the Yellow Sea and East China Sea. The results indicate that the species abundances, biomass, and diversity in spring 2011 were all lower than those in autumn 2000 and spring of 2001. Most of the dominant species have changed from 2001 to 2011, with the exception of the echinoderm Ophiura sarsii vadicola that was dominant in these years. Small-sized animal species have increased possibly due to gradual environment deterioration such as the pollution and the climate warmer.