全裸裸重唇鱼Gymnodiptychus integrigymnatus为鲤科裂腹鱼亚科特化等级的类群之一，是特化等级中分布纬度最低的种类。本种历史记录仅分布于云南高黎贡山西坡腾冲境内的龙川江上游少数支流（属伊洛瓦底江水系），被《中国物种红色名录》划分为极危物种。2000年至2006年中国科学院昆明动物研究所联合美国加州科学院对云南境内的高黎贡山进行了多次鱼类资源考察，在怒江州芒宽乡附近的高黎贡山东坡溪流（属怒江水系）新发现了全裸裸重唇鱼种群的分布。

为了探清本种在不同水系间的分化程度，昆明动物研究所鱼类组成员运用分子生物学（细胞色素b基因和D-loop序列）与形态度量学结合的方法，分析了9（4个怒江水系采集点，5个伊洛瓦底江水系采集点）个采集点共96个个体的数据。细胞色素b基因序列结果显示，来自伊洛瓦底江水系的9个个体与7个来自怒江水系水系的个体各自仅代表1个单倍型，遗传距离为1.97%，系统发育关系进一步证实本种与高度特化等级的裂腹鱼类群有更近的新缘关系。D-loop序列结果表明：本种有较高的遗传多样性，不同水系间的个体不共享单倍型；87.3%的遗传变异发生在不同水系间；不同水系的个体各自以较高的支持率形成单系。对6个可数量状和37个可量性状的分析表明，不能把不同水系的个体完全区别开来，但在某些性上存在可以区别开来的趋势。本种可能正在经历物种分化的过程。建议把本种列入高黎贡山国家自然保护区的重要保护物种并以两大不同水系为依据分别以不同进化显着单元加以优先保护，扩大保护区的范围，涵盖本种所有分布地区，加强本种的野外生态学和繁殖生物学研究。

原文出处：

Environmental Biology of Fishes  DOI: 10.1007/s10641-010-9629-6

Molecular and morphological analysis of endangered species Gymnodiptychus integrigymnatus (Teleostei: Cyprinidae)
Jian Yang, Xiaoyong Chen and Junxing Yang

Gymnodiptychus integrigymnatus is a critically endangered species endemic to the Gaoligongshan Mountains. It was thought to be only distributed in several headwater-streams of the Longchuanjiang River (west slope of the Gaoligongshan Mountains, belonging to the Irrawaddy River drainage). In recent years, dozens of G. integrigymnatus specimens have been collected in some streams on the east slope of the Gaoligongshan Mountains (the Salween drainage). We performed a morphological and genetic analyses (based on cytochrome b and D-loop) of the newly discovered populations of G. integrigymnatus to determine whether the degree of separation of these populations warrants species status. Our analysis from the cytochrome b gene revealed that nine individuals from the Irrawaddy drainage area and seven individuals from the Salween drainage area each have only one unique haplotype. The genetic distance between the two haplotypes is 1.97%. Our phylogenetic analysis revealed that G. integrigymnatus is closely related to highly specialized schizothoracine fishes. Analysis from the mitochondrial control region revealed that G. integrigymnatus has relatively high genetic diversity (π was 0.00891 and h was 0.8714), and individuals from different river drainages do not share the same haplotypes. The AMOVA results indicated 87.27% genetic variability between the Salween and Irrawaddy populations. Phylogenetic trees show two major geographic groups corresponding to the river systems. We recommend that G. integrigymnatus should be considered as a high priority for protected species status in the Gaoligongshan Mountains National Nature Reserve, and that the area of the Gaoligongshan Mountains National Nature Reserve should be expanded to cover the entire distribution of G. integrigymnatus. Populations of G. integrigymnatus from different river systems should be treated as evolutionarily significant units.