Effective conservation of threatened biota relies on accurate assessments and scientific guidance. As an unfortunate example, Chinese giant salamanders ( Andrias, CGS) remain critically endangered in nature. Misguided conservation efforts, e.g., commercial propagation and releasing of millions of likely non-indigenous or interspecific hybrids, have further compromised conservation initiatives. Limited information on wild populations of CGS poses a significant conservation challenge. Following 18-month long field monitoring, we now report the discovery of a wild population of CGS in a closed nature reserve in Jiangxi Province, China. Genomic assessments reveal its genetic distinctiveness and do not detect genetic admixture with other species. Based on morphological and molecular evidences, we describe this CGS as a new species Andrias jiangxiensis sp. nov. This is the only known species of CGS today with a genetically pure, reproducing, in situ population. This discovery emphasizes the important role that closed nature reserves play in protecting species, and the necessity of integrating long-term field monitoring and genetic assessments. It sets a new pathway for discovering and conserving endangered species, especially for those biotas that are similarly being extirpated by anthropogenic translocations and overexploitation.
濒危物种的有效保护需借助基础研究提供准确评估和行动依据。缺乏科学指导的保护行动可能会加速物种的灭绝。中国大鲵是一个不幸的实例：野外种群极度稀少，然而商业养殖导致了物种的人为迁移和杂交，同时大量未经遗传鉴定的养殖子代流入野外。以往基于“一个物种”认知下的保护措施收效甚微。野外种群数据的极度匮乏使得目前的保护行动难以开展。基于综合科学考察研究，该文报道在江西九岭山国家级自然保护区发现的大鲵野外种群。为期18个月的野外监测共记录包括成体、亚成体和新孵化幼鲵在内的700余尾个体，并连续两年观察到野外繁殖。基因组水平（简化基因组SNPs）分析支持该种群遗传分化显著且未受到其他省区大鲵的杂交污染。综合形态学和遗传分化证据，该研究描述一新种——江西大鲵 Andrias jiangxiensis sp. nov.。这是我国首个遗传身份明确且野外稳定繁殖的大鲵纯种种群。这一发现提示，相较于以水域范围设置的水生生物保护区，囊括整个山、水生态系统的自然保护区设置更为有效；同时，强调了综合野外监测和群体基因组分析手段对调查大鲵野外种群及明确遗传身份的必要性。该研究为受人类活动影响（如人为迁移，过度利用等）而濒临灭绝的物种制定和调整保护计划提供了参考和示范。.
Keywords: Conservation; Field monitoring; Genetic homogenization; Human translocation; Taxonomy.