利用形态学及mtDNA基因分子鉴定长须鲸和大村鲸

The morphological and mtDNA molecular identification of Fin whale and Omura’s whale

大型鲸类死亡个体,往往因腐烂程度较高或外部形态损坏,很难鉴定物种。2018年11月和2019年1月在江苏南通和浙江宁波各发现一头死亡须鲸。本文仔细辩别了两头须鲸的形态学特征,又应用分子生物学技术,分别得到903 bp和972 bp mtDNA控制区序列,以及467 bp和438 bp Cyt b序列。经GeneBank序列比对,南通样本与长须鲸相似度最高,达99%~100%;宁波样本与大村鲸相似度最高,达97%~99%。通过MEGA 7.0软件的最大似然法(ML)构建的系统发育树与Blast结果一致。综上,南通死亡须鲸鉴定为长须鲸,宁波死亡须鲸鉴定为大村鲸。同时,由于这两个物种在中国的分布信息比较缺乏,本研究证实了长须鲸在江苏省南通市及大村鲸在浙江省宁波市象山县的新分布。

It is difficult to morphologically identify large whale carcasses because they were highly decomposed or damaged.In November 2018 and January 2019,two dead decomposed baleen whales were found respectively in Nantong,Jiangsu Province and Ningbo,Zhejiang Province.Their morphological features were checked,and molecular biology technique was used,903 bp and 972 bp of mtDNA control region sequences as well as 467 bp and 438 bp of Cyt b sequences were obtained,respectively.After GenBank alignment,the samples from Nantong and Ningbo had the 99%-100%and 97%-99%similarity respectively and with the Fin whale(Balaenoptera physalus)and the Omura’s whale(B.omurai).The phylogenetic tree constructed by the maximum likelihood method in MEGA 7.0 software was consistent with the GeneBank alignment results.Based on two methods,the baleen whales in Nantong and Ningbo were respectively identified as Fin whale and Omura’s whale.The study confirmed the new distribution information of Fin whales in Nantong,Jiangsu Province and Omura’s whale in Xiangshan,Ningbo,Zhejiang Province.