Population structure and recruitment mechanism of Muraenesox cinereus leptocephali using otolith microsturucture and mitochondrial DNA sequences

利用耳石微结构和线粒体 DNA 序列研究 Muraenesox cinereus leptocephali 的种群结构和招募机制

• 批准号: 11660190
• 负责人: MOCHIOKA Noritaka
• 金额: $ 2.37万
• 依托单位: KYUSHU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11660190/
• 关键词: Muraenesox cinereus; Leptocephalus larva; Anguilliformes; Otolith microstructure; Mitochondrial DNA; Control region; Genetic variability; ミトコンドリアDNA; D-loop; ラベリング

The growth history and recruitment of Muraenesox cinereus were studied, based on growth increments in sagittal otoliths of leptocephali collected from Nobeoka (Miyazaki Pref.), Yatsushiro (Kumamoto Pref.), Onomichi (Hlroshima Pref.), Kamakura (Kanagawa Pref.) and off Goto Islands (East China Sea) in 1999 and in 2000. The periodicity of increment formation was confirmed by treating leptocephali with alizarin complexon and examining otoliths after a known time period. The formation rhythm of otolith increment was about 0.13/day in leptocephalus stage, 0.5/day in metamorphic stage and 1/day in juvenile stage, respectively. Examination of otoliths showed that leptocephali recruiting to Nobeoka Bay devided into two age groups, 150-200 and 250-300 days old. Back calculated hatching dates were distributed throughout most of the year, with a peak in summer and winter.Mitochondrial DNA sequences that include a part of the cytochrome b gene to the first half of the control region of Muraenesox cinereus leptocephali were determined to evaluate the population structure of the species. A total of 591 nucleotide site, including cytochrome b gene to the first half of the control region, was sequenced from specimens from Nobeoka, Yatsushiro, Kamakura and East China Sea. Out of 396 nucleotide sites on the control region, 31 (7.8%) variable, 16 haplotypes being found. Differences between nucleotide sequences ranged between 0.25 and 4.55% with average of 1.88%, indicating that the control region of the mitochondrial DNA in the species is characterized be high variability. The phylogenetic tree constructed by the neighbor-joining method shows neither significant geographic clusters. This result indicate that the present specimen might come from a single population.

根据采自日本宫崎县野冈冈的细头鳗矢状耳石的生长增量，八代（熊本县），尾道（Hlrosima Pref.），镰仓（神奈川县）1999年和2000年在后藤群岛（东海）附近海域进行了调查。通过用茜素络合剂处理钩端螺旋体并在一段已知的时间后检查耳石，证实了增量形成的周期性。耳石生长的形成节律为：细头期约0.13个/天，变态期约0.5个/天，稚贝期约1个/天。对耳石的检查表明，在野冈湾招募的细头蚴分为两个年龄组，150-200日龄和250-300日龄。通过对灰海鳗（Muraenesox cinereus leptocephali）线粒体DNA序列的测定，分析了灰海鳗（Muraenesox cinereus leptocephali）细胞色素B基因控制区前半部分的序列，并对该物种的种群结构进行了分析。对产自野冈、八代、镰仓和东海的日本血吸虫进行了包括细胞色素B基因在内的591个核苷酸序列测定。在控制区的396个核苷酸位点中，有31个（7.8%）变异，16个单倍型，核苷酸序列间的差异在0.25 ~ 4.55%之间，平均为1.88%，表明该物种线粒体DNA控制区具有高度变异性。用邻接法构建的系统发育树没有显示出明显的地理聚类。这一结果表明，目前的标本可能来自一个单一的群体。