短吻红舌鳎鱼卵、仔鱼的DNA条形码和形态学鉴定  

Identification of Cynoglossus joyneri eggs and larvae by DNA barcoding and morphological method

作　　者：周晓梦 郭书新 宋娜[1] 张秀梅[1,2] 

机构地区：[1]中国海洋大学海水养殖教育部重点实验室,山东青岛266003 [2]青岛海洋科学与技术国家实验室海洋渔业科学与食物产出过程功能实验室,山东青岛266072

出　　处：《生物多样性》2017年第8期847-855,共9页Biodiversity Science

基　　金：国家自然科学基金(31572227;41676153);青岛海洋科学与技术国家实验室鳌山科技创新计划项目(2015ASKJ01)

摘　　要：为了准确鉴定2015年7–10月青岛崂山青山湾鱼类浮游生物调查中采集的依形态学初步鉴定为某种舌鳎属的鱼卵、仔鱼样本,本实验同时采集青岛胶州湾短吻红舌鳎(Cynoglossus joyneri)和长吻红舌鳎(C.lighti)的成鱼样本为参照,通过线粒体COI基因测序分析,以及同山东半岛海域分布的6种舌鳎属鱼类的COI基因序列比对,开展了该舌鳎属鱼卵、仔鱼种类的鉴别分析,以期为今后舌鳎属鱼类的分类及其鱼卵、仔鱼的鉴别提供参考资料。形态学研究结果显示:鱼卵为圆球形浮性卵,直径0.68–0.87 mm(0.73±0.03 mm,n=50),卵膜单层,较薄、光滑透明,卵周隙较大,卵膜及卵黄囊均无特殊构造,油球6–15个,直径0.04–0.10 mm(0.07±0.01 mm,n=50),圆形,大小不一,多位于卵黄囊中与胚体相对的一侧,既有聚集分布也有分散分布;仔鱼的2条冠状幼鳍及右眼移位过程中体长、色素分布等的特征和变化是此鱼种仔鱼鉴别的最明显特征。遗传学分析结果显示:该种舌鳎属样品(Cynoglossus sp.)与短吻红舌鳎和长吻红舌鳎的遗传距离最为接近,三者K2P遗传距离为0.006–0.009;短吻三线舌鳎(C.abbreviatus)与紫斑舌鳎(C.purpureomaculatus)亲缘关系最近,两者K2P遗传距离仅为0.002。以带纹条鳎(Zebrias zebra)为外类群构建的NJ系统发育树显示,该种舌鳎属样品与短吻红舌鳎和长吻红舌鳎以及短吻三线舌鳎与紫斑舌鳎分别聚为一支,其他种类各聚为一支。综合形态特征和COI基因比对结果,确定该舌鳎属鱼卵、仔鱼样品为短吻红舌鳎。This study was designed to accurately identify Cynoglossus eggs and larvae（Cynoglossus sp.）, and to accumulate base data for further study on the taxonomy and early identification of Cynoglossus fishes. Cynoglossus sp. samples were collected in Qingshan Bay, Qingdao, between May and October 2015. Three eggs, 3 larvae and a total of 5 individuals from 2 species（C. joyneri and C. lighti） in the Jiaozhou Bay area were barcoded using COI, sequenced, and compared with 6 Cynoglossus species found in the Shandong Peninsula and recorded in Gen Bank. Under a light microscope, the egg had a circular shape and floated within a wider perivitelline space; eggs ranged in diameter from 0.68 to 0.87 mm with a mean diameter of 0.73±0.03 mm; eggs had a single layer membrane and were smooth and transparent; the oil globules were located opposite the yolk sac, ranged from 6 to 15 in number, and diameter ranged from 0.04 to 0.10 mm（mean diameter： 0.07±0.01 mm）; there were obvious characteristics including the 2 dorsal fin rays and pigmentation and body length changes in the period of metamorphosis for larvae identification. Results of genetic analysis showed that the average K2 P distances pairwise-species in Cynoglossus sp., C. joyneri and C.lighti ranged from 0.006 to 0.009, and was 0.002 for C. abbreviatus and C. purpureomaculatus. The two groups were placed in two different clades with the support of a high bootstrap value and had a close genetic relationship, separately. The neighbor-joining（NJ） phylogenetic trees were constructed for COI gene sequences of 8 species using MEGA 6.0, and Zebrias zebra was included as an outgroup. The above analysis and results showed that the Cynoglossus sp. is C. joyneri.

关 键 词：舌鳎属 同种异名 鱼类浮游生物 COI 鉴别 

分 类 号：S917.4[农业科学—水产科学]