梭鱼幼鱼选择温度的研究

梭鱼幼鱼选择温度的研究张梅英岳玉环（中国医科大学实验动物部,沈阳１１０００１）（吉林农业大学动物科学系,长春１３０１１８）侯文礼（东北师范大学环境科学系,长春１３００２４）ＴｅｍｐｅｒａｔｕｒｅｓｅｌｅｃｔｉｏｎｆｏｒＬａｒｖａｏｆＬｉｚａｈａｅｍａ...     

Skeletal structure as taxonomic tool for identification of mullet species (Teleostei: Mugilidae) from Aceh waters,Indonesia

Many members of the mullets (family Mugilidae) are very similar morphologically, hence the possibility of taxonomic misidentification. This study involved the use of skeleton structure to distinguish four species of mullets, including Cremugil crenilabis, Liza macrolepis, Moolgarda engelii, and Mugil cephalus, harvested from Aceh waters, Indonesia. The mullets samples were collected from 10 locations, and a total of 10 samples were taken randomly as representatives of each species. The skeletal sample was prepared using the dry method. The results showed the presence of 8 pairs of ribs in C. crenilabis and L. macrolepis, while M. engelii had 9, with 10 in M. cephalus. In addition, the origin of the haemal canal of C. crenilabis is at the 12th vertebrae, extends to the 23rd, while for the other three species it starts at the 10th and extends to the 23rd. In addition, C. crenilabis possesses 12 haemal canals, but the rest have 14. The haemal canal is present in the last precaudal vertebrae of all specimens, except C. crenilabis, whose epural bone in the caudal skeleton is small and located far from the preural, while a larger and distinctly attached form is observed in the rest. Furthermore, L. macrolepis possess a pair of diapophyses, which laterally extend in the 2nd vertebrae. This bone is absent in the three other species. The presence of diapophyses, the number of ribs and haemal canals and the location of the epural bone in the caudal skeleton, and the condition of frontal attachment to the sphenotic are the important characters in distinguishing the four investigated species of mullets.     

梭鱼幼鱼热忍受温度的研究

自然界水体温度变化通常表现为缓慢的渐进过程,因而水生生物能长期适应并稳定地生活在其中。然而,随着热（核）电站的兴建,许多湖泊、水库、河流、沿海水域成为其冷却水源,温排水造成该水域水温升高,并不同程度地危害水生生物资源,形成热污染。国外早在５０年代已开...     

长江口鮻矢耳石形态特征及质量与年龄的关系

为研究长江口鮻矢耳石形态特征及其质量与年龄的关系,2017年2—6月从长江口水域采集鮻358尾,解剖并提取耳石324对,并对其形态学参数进行测量分析.结果表明:鮻矢耳石具有基叶和翼叶,中央听沟明显,矢耳石的大小和形状随个体生长变化明显,矢耳石由边缘规则的圆润瓜子状渐变为褊窄的叶片状,边缘波浪状突起逐渐变多.矢耳石平均密度为1.52 mg·mm^-2,平均矩形趋近率为0.68,耳石长占其体长的0.021%~0.047%,耳石宽占其体长的0.009%~0.021%,耳石质量占其体质量的0.045‰~0.731‰.鮻矢耳石长(OL)、宽(OW)、质量(OM)均与体长呈显著相关,耳石宽与耳石质量函数关系式的决定系数(R^2)最高(0.928).耳石质量与体长(BL)最佳拟合方程为幂函数:OM=0.0009BL1.8737(R2=0.967);耳石质量与年龄(A)以及体长与年龄的最佳拟合方程为多项式:OM=2.9262A^2+4.8437A+2.1894(R^2=0.847);BL=-3.2248A^2+102.54A+38.373(R^2=0.858),矢耳石质量与年龄呈显著线性相关,用耳石质量与年龄关系估算的年龄与从耳石上直接读取的年龄无显著差异,矢耳石质量可以作为鉴定鮻年龄的有效辅助手段.     

Larval development of the back keeled mullet Liza carinata

The sex ratio of the fish used in this study, was 1:1.5 females to males. Natural spawning of the keelback mullet, Liza carinata, in captivity was possible and occurred between December and February. The mean fertilized egg diameter of L. carinata was 0.8±.051 mm. Hatching took place after 36 h at 23°C. The mean total length of the just-hatched larvae was 2.0±0.179 mm. Larval developmental stages, growth, and morphological changes of L. carinata were described on the basis of a series of specimens (391 in total) reared from days 1 to 89 after hatching. Details of the larval developmental stages were drawn and photographed, with special reference being taken of morphological transformations. Larvae completed yolk absorption on the sixth day after hatching, and opened their mouths on day 4. Notochord flexion started on the sixteenth day at 5.0 mm total length. Transformation from larval to juvenile stage occurred between days 30 and 51 after hatching. The maximum size of larvae and the minimum size of juveniles which appeared during the transitional period were 19 and 9.9 mm TL, respectively. By day 51, all the larvae had changed into juveniles with a mean TL of 29.3±6.429 mm. The juveniles started to change into young adults with three anal spines by day 88 at a TL of 62 mm. This revised version was published online in September 2006 with corrections to the Cover Date.