01940nas a2200181   4500008004100000020001400041245016300055210006900218260000800287300001200295490000700307520134000314100001201654700001201666700001801678700001601696856004601712       2016                        eng d  a1738-526100a<i>Dracograllus trukensis </i>sp nov (Draconematidae: Nematoda) from a seagrass bed (Zostera spp.) in Chuuk Islands, Micronesia, Central Western Pacific Ocean0 aiDracograllus trukensis isp nov Draconematidae Nematoda from a s  cSep  a343-3540 v513 aA new species of free-living marine draconematid nematode, Dracograllus trukensis sp. nov., is described based on the specimens collected from the sediments of a intertidal seagrass bed from Chuuk Islands, Micronesia. Dracograllus trukensis sp. nov. differs from other species of the genus by the combination of the following characteristics: the presence of numerous minute spiny ornamented body cuticular annules in both sexes, eight cephalic adhesion tubes inserted on the head capsule in both sexes, the presence of stiff posteriorly directed setae anterior to posterior adhesion tubes in both sexes, the shape (large, elongated, open loop-shaped in male and large, elongated, closed loop-shaped in female) and position (longer ventral arm extending to the first body annule in male) of amphideal fovea, shorter spicule length (34-42 mu m), the presence of sexual dimorphism in shape and length of the non-annulated tail terminus, and number of posterior sublateral adhesion tubes (10 in male and 13-15 in female) and posterior subventral adhesion tubes (8-10 in male and 9-11 in female). A comparative table on the biogeographical and ecological characteristics of the species of Dracograllus is presented. This is the first taxonomic report on the genus Dracograllus from Chuuk Islands, Micronesia, central western Pacific Ocean.1 aMin, W.1 aKim, D.1 aDecraemer, W.1 aRho, H., S.  uhttps://nematodes.myspecies.info/node/71802045nas a2200193   4500008004100000020001400041245013300055210006900188260000800257300001200265490000700277520145000284100001401734700001301748700001201761700001801773700001401791856004601805       2009                        eng d  a1016-847800aMonophyly of the family Desmoscolecidae (Nematoda, Demoscolecida) and Its Phylogenetic position inferred from 18S rDNA sequences0 aMonophyly of the family Desmoscolecidae Nematoda Demoscolecida a  cMay  a515-5230 v273 aTo infer the monophyletic origin and phylogenetic relationships of the order Desmoscolecida, a unique and puzzling group of mainly free-living marine nematodes, we newly determined nearly complete 18S rDNA sequences for six marine desmoscolecid nematodes belonging to four genera (Desmoscolex, Greeffiella, Tricoma and Paratricoma). Based on the present data and those of 72 nematode species previously reported, the first molecular phylogenetic analysis focusing on Desmoscolecida was done by using neighbor joining (NJ), maximum parsimony (MP), maximum likelihood (ML) and Bayesian inference (BI) methods. All four resultant trees consistently and strongly supported that the family Desmoscolecidae forms a monophyletic group with very high node confidence values. The monophyletic clade of desmocolecid nematodes was placed as a sister group of the clade including some members of Monhysterida and Araeolaimida, Cyartonema elegans (Cyartonematidae) and Terschellingia longicaudata (Linhomoeidae) in all the analyses. However, the present phylogenetic trees do not show any direct attraction between the families Desmoscolecidae and Cyartonematidae. Within the monophyletic clade of the family Desmoscolecidae in all of the present phylogenetic trees, there were consistently observed two distinct sub-groups which correspond to the subfamilies Desmoscolecinae [Greeffiella sp. + Desmoscolex sp.] and Tricominae [Paratricoma sp. + Tricoma sp].1 aHwang, U.1 aChoi, E.1 aKim, D.1 aDecraemer, W.1 aChang, C.  uhttps://nematodes.myspecies.info/node/122