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1.
A new species,Clathrocorys gracilis nov. spec. of Tripocyrtidae (Radiolarians: Nassellaria) from surface water in northern South China Sea, is described in this paper. The new species has four radial beams arising from the cephalic base centre, each foot with cup-shaped structure and ramified bar in the proximal section (near cephalic base), and each wing with a large mesh in the middle, a medium mesh and a small mesh on each side respectively. Project supported by the NSFC (No. 40276044) and the Chinese Academy of Sciences (No. KSCX2-SW-101B).  相似文献   

2.
A new species of free-living nematode, Pseudolella major sp. nov. is described from the intertidal mudflats of Ximen Island in the East China Sea. Pseudolella major sp. nov. is characterized as follows: body length ~1 300 μm; short cephalic setae, 2–3 μm long; amphidial fovea loop-shaped with elongated ventral branch; ventral branch 50–60 μm long and extending past the base of buccal cavity; buccal cavity cylindrical with arching or spherical base; three heavy outwardly-curving odontia with blunt tips located at anterior of buccal cavity; pharynx short with posterior bulb; ventral gland cell elongate oval-shaped, located posterior to pharyngo-intestinal junction; excretory pore situated at the level of the middle of buccal cavity; tail conical to cylindrical; spicules arched, with double-cephalate proximal end; gubernaculum with a strong dorsal caudal apophysis.  相似文献   

3.
A new monostiliferous hoplonemertean, Psummamphiporus microocelli sp. nov., is described. It differs from the single species of genus Psammamphiporus, P. elongatus, in being without a frontal organ and cephalic furrows, the stylet basis being conical rather than cylindrical.  相似文献   

4.
A new monostiliferous hoplonemertean,Psammamphiporus microocelli sp. nov., is described. It differs from the single species of genusPsammamphiporus, P. elongatus, in being without a frontal organ and cephalic furrows, the stylet basis being conical rather than cylindrical. The project supported by National Natural Science Foundation of China.  相似文献   

5.
A new free-living marine nematode species of the genus Rhinema belonging to the family Monoposthiidae was collected from marine sediments in the Qiongzhou Strait of the South China Sea,and it is described here as Rhinema longispicula sp.nov.The new species is characterized by coarsely annulated cuticle with 12 longitudinal ridges(alae) marked as reversed V-shaped.The first and second annuli broader and form a kind of a cephalic capsule.The amphideal fovea circular,situated in the middle of the broad second annulus,not surrounded by dense annulations.Buccal cavity cylindrical with a large dorsal tooth.Pharynx with a prominent anterior pharyngeal bulb and an elongated terminal bulb.Elongate spicules strongly curved,with cephalated proximal end and pointed distal end.Gubernaculum boat-shaped,without apophysis.A long and blunt precloacal seta present.Female with two opposed,outstretched ovaries.  相似文献   

6.
Huang  Mian  Sun  Jing  Huang  Yong 《中国海洋湖沼学报》2019,37(1):273-277

A new species of free-living marine nematode of the genus Daptonema Cobb, 1920 is described from the sublittoral sediment of the Jiaozhou Bay, Qingdao. Daptonema parabreviseta sp. nov. is characterized by having narrowed anterior end; small funnel-shaped buccal cavity; short cephalic setae; spicules with bulbiform proximal end and pointed distal end; gubercunalum tubular shape with a blunt dorsal apophysis. The female genital system presents a spacious postvulval sac. The new species closely resembles Daptonema brevisetosum Thanh & Gagarin, 2009. However, it differs from Daptonema brevisetosum by having relatively narrowed head (10 μm vs 20 μm); spicules with bulbiform proximal end and pointed distal end, not bifurcated at distal end. Female genital system with a spacious postvulval sac (vs absent).

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7.
This study records length-weight relationships(LWRs)for eleven commercially important marine catfi sh species of the family Ariidae(sea catfi shes)and Plotosidae(eel catfi shes)from the northern Arabian Sea coast of Pakistan.The specimens were sampled from December 2014 to November 2015,using bottom trawls with various mesh sizes by commercial vessels.The species were Nemapteryx caelatus,Sciades sona,Arius gagora,Batrachocephalus mino,Netuma thalassina,N.bilineata,Osteogeneiosus militaris,Plicofollis dussumieri,P.tenuispinis,Plotosus limbatus,and P.lineatus.Of the eleven species,two species A.gagora and N.bilineata were recorded for the fi rst time and LWRs for four species A.gagora,N.bilineata,S.sona,and B.mino still have no data in the Fish Base database.In addition,new maximum length for each of the three species N.bilineata,O.militaris and B.m ino was also found.  相似文献   

8.
针对现有的大量古建筑三维模型缺乏语义信息,不利于精细化和智能化管理等问题,对城市地理标记语言(City Geography Markup Language, CityGML)定义的建筑物模型进行了语义扩展,提出了一种从古建筑几何模型自动识别语义对象并转化为CityGML扩展模型的方法。首先,总结我国明清古建筑构件的共有特征,并使用CityGML的应用领域扩展机制增加斗拱、梁、柱、台基等古建筑通用对象的几何和语义表达。其次,利用古建筑Mesh模型各面片的法向量、坐标范围等特征和自定义规则提出了一套古建筑屋顶、墙面、立柱、门窗等语义对象自动识别方法。最后,依据CityGML扩展模型设计规范,从识别对象自动构建出几何语义一体化表达的古建筑三维模型。采用2个不同风格的古建筑模型进行语义对象提取和CityGML模型生成实验,使用本文提出的Mesh模型到CityGML LoD3扩展语义模型转换方法能够自动提取屋顶、墙面、台基等9类语义对象,每个Mesh模型能转换并生成400多个包含语义信息的平面多边形,95%以上的面片能正确识别。结果表明本文设计的CityGML扩展模型能够有效支持古建筑模型典型构件的显式语义表达,并且识别规则和转换方法能够支持Mesh模型大多数平面对象的提取,有利于CityGML模型的自动化生成和精细化管理。  相似文献   

9.
Selection of net with a suitable mesh size is a key concern in the quantitative assessment of zooplankton, which is crucial to understand pelagic ecosystem processes. This study compared the copepod collecting efficiency of three commonly used plankton nets, namely, the China standard coarse net(505 μm mesh), the China standard fine net(77 μm), and the WP-2 net(200 μm). The experiment was performed at six stations in the Bohai Sea during the autumn of 2012. The coarse net substantially under-sampled small individuals(body widths 672 μm) and led to the lowest species number in each tow, whereas the fine net collected all small copepod species but failed to collect rare species. The WP-2 net appeared to be a compromise of the two other nets, collecting both small copepods and rare species. The abundance of copepods collected by the coarse net(126.4 ± 86.5 ind m~(-3)) was one to two orders of magnitude lower than that by the WP-2 net(5802.4 ± 2595.4 ind m~(-3)), and the value of the fine net(11117.0 ± 4563.41 ind m~(-3)) was nearly twice that of the WP-2 net. The abundance of large copepods(i.e., adult Calanus sinicus) in the three nets showed no significant differences, but the abundance of small copepods declined with decreasing mesh size. The difference in abundance resulted from the under-sampling of small copepods with body widths 672 μm and 266 μm by the coarse and WP-2 nets, respectively.  相似文献   

10.
2011 年8 月在广西靖西县安德乡-洞穴地下水中采到4 尾标本,经鉴定为间条鳅属一新种,命名为小间条鳅Heminoemacheilus parva.新种区别于同属已知种郑氏间条鳅H. zhengbaoshani 的特征为无眼,无鳞,无色透明,侧线完全,胸鳍末端超过胸鳍基部与腹鳍基部之间的中点.区别于同属另一已知种透明间条鳅H. hyalinus 的特征为:体细长,体长为体高的4.8~7.3 倍;头较长,体长为头长的3.1~3.6 倍;尾柄细长,尾柄长为尾柄高的1.6~2.4 倍.  相似文献   

11.
基于HASM算法的DEM建模与应用试验   总被引:2,自引:0,他引:2  
以曲面论为理论基础建立的高精度曲面模型(High Accuracy Surface Modelling,HASM)其插值精度较传统方法提高了多倍,为CAD和GIS系统提供了更有效的曲面模拟工具。但由于HASM需要对研究区域用相同的网格分辨率模拟,且对研究区域内每个网格点建立偏微分方程,因此,计算量和存储量问题严重制约其推广使用。适应法网格精化技术,可以根据模拟区域的地形复杂度或者精度要求调整网格分辨率,即在地形平坦区域用粗网格模拟,在复杂区域用细网格模拟。基于此理论,我们建立了适应算法的HASM。对甘肃省董志塬进行的DEM模拟表明,HASM适应算法能在保证模拟精度的同时,极大地减少了计算时间和降低存储量,从而有效解决了HASM推广使用的计算量和存储量瓶颈问题。  相似文献   

12.
Dammam City is one of the gorgeous coastal areas in the Arabian Gulf of Saudi Arabia.The present study aimed to ex-amine one of the copepod species infecting the rosy goatfish that represents a highly consumed fish species by the local population in the Arabian Gulf.The copepod species isolated from the infected fish specimens belong to the family Taeniacanthidae and was iden-tified as Irodes parupenei Ho and Lin(2007),primarily based on its morphological,morphometric,and ultrastructural characteris-tics,especially the structures of the dorsal cephalic area,segmentation of the first antenna,the absence of the maxilliped claw in the fe-male specimens,and the setation and spinulation of the legs 2-4 for the adult females are of great significance in the taxonomic iden-tification.The 18S rRNA gene sequence was analyzed to ensure the precise identity and exact taxonomic status of the copepod species.The result showed that this copepod species belong to Taenicanthidae and closely related to Irodes sauridi(gb|JF781550.1)in the same taxon.More details on the specificity of the goatfish for Irodes species and identifying these parasitic taxa using molecular analysis are given in the present study.  相似文献   

13.
We describe a new species of gerreid fish,Gerres septemfasciatus,based on four specimens collected from the northern South China Sea.G.septemfasciatus most closely resembles G.limbatus in general appearance.However,G.septemfasciatus is distinguished from the latter and other congeners by having 3 to 3.5 scales between the base of the fifth dorsal spine and lateral line.This species has a distinctive color pattern,including 7-8 regular,vertical,blue-grayish bands on its side.The distribution of this species ...  相似文献   

14.
不同结构网囊特性的初步研究   总被引:1,自引:0,他引:1  
为了测定不同拖网网囊结构对网囊的几何形状、同目张开、网目形状和拖网阻力的影响,设计和制作了4种网囊,一种是传统的菱形同目(DM)网囊,另三种是新型网囊:方形同目(SM)网囊,菱、方形网目混合二片式(DSM2)网囊和菱、方形同目混合四片式(DSM4)网囊。于1996年9月11~12日在中山大学试验水槽进行了同模试验,结果表明:1)各网囊阻力相差不大,且随拖速和渔获的增加而增大。2)新型网囊的几何形状和同目的张开及其形状均优于传统菱形网目网囊。3)空网时,各种网囊均呈圆筒状。当网囊中有了渔获后,传统菱形同目网囊的端部变为球状,除了球状部分的网目有较大张开外,其余同目张开很小,网囊使用直径也小,而新型网囊始终保持筒状,且网目充分张开,网囊使用直径也大。4)新型例翼的几何形状及使用直径和网目的张开及形状几乎不受拖速大小、有无渔获和渔获多少的影响。  相似文献   

15.
INTRODUCTIONPufferfishesofthegenusTakifugu (Tetraodontiformes,Tetraodontidae)aremainlydistributedalongthecoastalregionsofChina ,JapanandKoreaandarecommerciallyimportanttothesecoun tries .Over 2 0specieshavebeenrecordedintheYellowSeaandtheEastChinaSea (Cheng…  相似文献   

16.
方目网囊对蓝圆鲹和多齿蛇鲻的选择性比较   总被引:1,自引:0,他引:1  
为检测方目网囊对蓝圆鱼参和多齿蛇鲻的选择作用 ,2 0 0 0年 1 1~ 1 2月在南海北部海域试验了 4种目大的方目网囊。结果表明 ,方形网目网囊有利于释放纺缍形 (如蓝圆 鱼参)、圆形或近圆形 (如多齿蛇鲻 )两种形体鱼类的小、幼鱼 ,且对后者的释放效果更好。当网囊目大分别为 45、5 0mm时 ,蓝圆鱼参的5 0 %选择体长 (L0 .5)分别为 1 2 1 2 2、1 2 8 77mm ;当网囊目大分别为 40、45、5 0mm时 ,多齿蛇鲻的L0 5分别为 1 2 4 1 2、1 2 6 75、1 3 9 3 2mm。通过不同目大网囊对蓝圆鱼参、多齿蛇鲻选择性比较分析 ,发现 5 0mm目大方目网囊的选择效果好于 40、45mm目大的网囊 ,因此 ,在南海区拖网渔业中采用 5 0mm目大的方目网囊是必要的 ,同时建议将 1 5 0mm作为蓝圆鱼参、多齿蛇鲻的最小可捕叉长标准。  相似文献   

17.
根据疏目拖网逐目和逐个编结周期或剪裁循环地装配的要求,提出了先计算口门每目和网翼或网缘的每编结周期或剪裁循环的配纲长度,然后再计算出整段口门和网翼或网缘的配纲长度之设计计算方法。  相似文献   

18.
Based on the anatomical study of leaf cuticles of Cordaites from the Lower Permian Shanxi Formation in Baode of Shanxi, the author analysed the epidermal characters of Cordaites in this area. On the base of the abundant compressions and laboratory studies, the author complemented some new data of the cuticular characters of the species Cordaites baodeensis Sun for its study of taxonomy. Meanwhile, the author newly discovered a number of sporopollen fossils associated with the mega-plants of Cordaitales, described 9 species of 6 genera. The palynological data can provide a supp lement evidence for defining the age of C. baodeensis and its associated plants to be Early Permian.  相似文献   

19.
本文根据桐庐县瑶琳镇和平村上二叠统雾林山组(相当于龙潭组)剖面第⑨层中发现的一种奇待的种子化石,经标本描述鉴定,确认其为种子化石的新属种,而建立的奇丽桐庐籽(新属、新种)Tonglucarpusspectabilisgen.etsp.nov,归于晚二叠世。  相似文献   

20.
Based on the anatomical study of leaf cuticles of Cordaites from the Lower Permian Shanxi Formation in Baode of Shanxi,the author analysed the epidermal characters of Cordaites in this area.On the base of the abundant compressions and laboratory studies,the author complemented some new data of the cuticular characters of the species Cordaites baodeensis Sun for its study of taxonomy.Meanwhile,the author newly discovered a number of sporopollen fossils associated with the mega-plants of Cordaitales,described...  相似文献   

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