金线鲃属（Sinocyclocheilus）是中国西南喀斯特地区特有的淡水鱼类，也是世界上洞穴鱼类物种最为丰富的辐射演化类群。其多样的物种组成和显著的生态分化，为研究极端环境适应与多倍体演化提供了理想模型。与经典二倍体洞穴模式物种墨西哥丽脂鲤（Astyanax mexicanus）相比，金线鲃在系统发育背景、多倍体起源及表型演化路径等方面具有独特性。本文系统梳理了其分类与系统发育关系，总结了从地表到典型洞穴种的连续生态类型及表型变异特征，重点归纳了视觉和色素退化、鳞片减少及感觉代偿等关键适应性状的分子机制。在此基础上，探讨多倍体化在基因冗余、表达调控重塑及适应性演化中的作用。综合现有证据，金线鲃的洞穴适应性进化呈现多路径趋同和性状协同权衡的特征，多倍体背景可能为其提供重要的遗传基础。本文进一步深化了对洞穴鱼类适应性进化及多倍体物种演化机制的认识，同时阐明该类群具备重要研究潜力，可为解析基础生物学核心过程提供独特的演化研究视角与天然突变谱系。

The cyprinid genus Sinocyclocheilus, endemic to the karst regions of southwestern China, represents the world's most species-rich cavefish radiation. Its remarkable species diversity and ecological divergence provide an ideal model for studying extreme environmental adaptation and polyploid evolution. Compared to the classic diploid cavefish model Astyanax mexicanus, Sinocyclocheilus exhibits a unique phylogenetic background, an allotetraploid origin, and distinct phenotypic evolutionary trajectories. In this review, we outline its taxonomy and phylogeny and summarize the continuous ecological morphs from surface to obligate cave dwellers alongside their phenotypic variations. We highlight the molecular mechanisms underlying key adaptive traits—including eye degeneration, pigmentation loss, scale reduction, and sensory compensation—and discuss the role of polyploidization in gene redundancy, expression regulation, and adaptive evolution. Current evidence reveals that cave adaptation in Sinocyclocheilus involves convergence through multiple evolutionary routes and synergistic trait trade-offs, which are largely facilitated by its polyploid genomic background. This review deepens our understanding of cavefish adaptation and polyploid evolution, highlighting the potential of this genus in providing valuable evolutionary perspectives and natural mutation pedigrees for deciphering fundamental biological processes.