Conservational studies for the endangered species, Tribolodon nakamurai(Pisces, Cyprinidae) based on ecological surveys and genetic analyses of present populations.

基于生态调查和现有种群遗传分析的濒危物种中村三齿鱼（双鱼座，鲤科）的保护研究。

• 批准号: 17510192
• 负责人: HANZAWA Naoto
• 金额: $ 2.05万
• 依托单位: Yamagata University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-17510192/
• 关键词: endangered species; cyprinid species; ecological survey; food habit; DNA markers; genetic diversity; population structure; conservation; ウケクチウグイ

Tribolodon nakamurai is an endangered species distributed only in some rivers flowing to Sea of Japan in southern Tohoku District. Its behavior is unknown, because its population-density is extremely low in any habitats. In this study, we conducted ecological surveys for T. nakamurai and T. hakonensis as a control species in Mogami River Systems, Yamagata and Agano River Systems, Fukushima where Hanzawa and Taniguchi (1982) had ever investigated. Using living and dead samples, we also carried out feeding experiments and population analyses based on two different DNA markers, clarified its behavior and population structures, and estimated degree of emergency of extinction.Although some individuals of T. nakamurai could be collected in downstream of Mogami and upperstream of Agano Rivers, less individuals were confirmed in upperstream of Mogami River. In 2006 and 2007, no individual of T. nakamurai was observed in known spawning ground in the river, revealing that its spawning was inhibited by abnormal warm in the winters. Observation of living individuals showed that the species is a fish-eater, suggesting that the food habit is related to its extremely low population-density. Mitochondrial DNA analysis showed that Mogami and Agano populations are genetically differentiated and genetic diversity is considerably low in all populations. Similarly, microsatellite analysis showed that genetic diversity is remarkably low in all populations. The both analyses detected a hybrid between T. nakamurai and T. hakonensis from downstream of Mogami River for the first time. From these results, we concluded that 1) number of individuals of T. nakamurai considerably decreased in both present populations, 2) there is the possibility that their fitness has decreased by inbreeding and introgression, 3) Mogami and Agano River populations should be regarded as different conservation units, and 4) their spawning grounds and habitats should be immediately conserved.

中村三齿兽是濒危物种，仅分布于东北地区南部流向日本海的部分河流。它的行为未知，因为它的种群密度在任何栖息地都极低。在这项研究中，我们对 Hanzawa 和 Taniguchi (1982) 曾经调查过的山形最上河流域和福岛县阿贺野河流域的 T. nakamurai 和 T. hakonensis 作为对照物种进行了生态调查。利用活体和死亡样本，我们还根据两种不同的DNA标记进行了摄食实验和种群分析，阐明了其行为和种群结构，并估计了灭绝的紧急程度。最上川及阿贺野川上游，最上川上游确认个体较少。 2006年和2007年，在河中已知的产卵场没有观察到中村砗磲个体，这表明其产卵受到冬季异常温暖的抑制。对现存个体的观察表明，该物种是食鱼动物，这表明这种饮食习惯与其极低的种群密度有关。线粒体 DNA 分析表明，最上种群和阿贺野种群存在遗传分化，所有种群的遗传多样性都相当低。同样，微卫星分析表明，所有种群的遗传多样性都非常低。两项分析均首次在最上川下游发现了中村毛龟和箱根毛龟的杂交种。从这些结果中，我们得出结论：1）当前两个种群中 T. nakamurai 的个体数量显着减少，2）它们的适应性可能因近交和基因渗入而下降，3）最上和阿贺野河种群应被视为不同的保护单位，4）应立即保护其产卵场和栖息地。

项目成果

ミトゲノム解析に基づくコイ科Megalobrama属魚類とその近縁群の系統類縁関係

基于线粒体基因组分析的鲂科鱼类及其相关类群的系统发育关系

• 发表时间: 2006
• 作者: Okuda H;Manabe T;Yanagita T;Matsuzaki S;Bando Y;Katayama T;Wanaka A;Tohyama M;井元順一・斉藤憲治・宮正樹・西田睦・半澤直人.
• 通讯作者: 井元順一・斉藤憲治・宮正樹・西田睦・半澤直人.

Phylogenetic relationships of Megalobrama fishes and related groups in Cyprinidae based on mitogenomic analysis

基于线粒体基因组分析的鲂鱼及鲤科相关类群的系统发育关系

• 发表时间: 2006
• 作者: Imoto J;K Saitoh;M Miya;M Nishida and N Hanzawa.
• 通讯作者: M Nishida and N Hanzawa.

Genetic divergence and phylogenetic independence of Far Eastern species in the subfamily Leuciscinae(Pisces : Cyphnidae) inferred from mitochondrial DNA analysis

从线粒体 DNA 分析推断远东 Leuciscinae 亚科（双鱼座：Cyphnidae）物种的遗传分化和系统发育独立性

• 发表时间: 2007
• 期刊: Genes and Genetic Systems 82
• 作者: Sasaki T;Y P Kartavtsev;S N Chiba;V V Sviridov and N Hanzawa.
• 通讯作者: V V Sviridov and N Hanzawa.

Phylogeny of leuciscinae fishes widely distributed in Northern Hemisphere based on mitochondrial genomes.

基于线粒体基因组的北半球广泛分布的亮鱼科鱼类的系统发育。

• 发表时间: 2007
• 作者: Imoto;J・K;Saitoh・Y;P;Kartavtsev・K;Nakamura・M;Miya・M;Nishida・N;Hanzawa
• 通讯作者: Hanzawa

Inferences in Leucuscinae(Pisces, Cyprinidae) phylogeny and taxonomy based on cytochrome b sequence distances and enzyme loci diversity

基于细胞色素b序列距离和酶位点多样性的白鳢亚科（双鱼座、鲤科）系统发育和分类学推论

• 发表时间: 2007
• 期刊: Korean Journal of Genetics 29(4)
• 作者: Kumamoto N;Matsuzaki S;Inoue K;Hattori T;Shimizu S;Hashimoto R;Yamatodani A;Katayama T;Tohyama M.;Kartavtsev Y P and N Hanzawa.
• 通讯作者: Kartavtsev Y P and N Hanzawa.