洞穴鱼类:概念、多样性及研究进展

洞穴鱼类是淡水鱼类中一个特殊的生态类群,其生活史的自然完成离不开洞穴或地下水环境。洞穴鱼类可分为典型和非典型两种类型,前者具有易辨识的特殊适应性形态结构(如眼消失、身体透明等),后者此类特征不明显。目前世界典型洞穴鱼类共记录有107种,其中鲤形目和鲇形目的种类最多,分别占49.5%和24.3%;在科级水平上以鲤科和爬鳅科最为丰富。东南亚和中南美是洞穴鱼类多样性最高的地区,有着世界上75.0%的典型洞穴鱼类。中国的洞穴鱼类具有物种多样性高、但集中出现在个别类群(如金线鲃属(Sinocyclocheilus)和高原鳅属(Triplophysa))、物种分化强烈、分布范围狭窄、种群数量小等特点。洞穴鱼类学是一门交叉科学,研究涉及系统学、生态学、生理学、保护生物学等众多学科领域,但目前研究仍多围绕演化问题展开。中国洞穴鱼类研究还处于系统分类和区系研究水平,其他有关学科的研究有待开展。

Cavefishes: concept, diversity and research progress

Cavefishes, or hypogean fishes, are a distinctive group of freshwater fishes. Their life histories unseverably bind them to a cave or underground water body. Some of them, termed troglobites, have specific characteristics adapting them to subterranean life. Other hypogean fishes, the troglophiles, do not possess such specialized characteristics. There are 107 typical troglobite fish species known in the world. Of these, Cypriniformes and Siluriformes have the most troglobite fish species, accounting for 49.5% and 24.3% of the total, respectively. At the family level, Cyprinidae and Balitoridae have the richest species diversity of troglobite fishes. Hypogean fishes are predominantly distributed in southeastern Asia, and central and south- ern America, where 75.0% are found. In China, rich species diversity occurs in only a few genera, namely Sinocyclocheilus and Triplophysa, characterized by narrow distributions, intense speciation, and small popu- lation size. Research on cavefish is a cross-disciplinary subject involving systematics, ecology, physiology, and conservation biology. At present, the study mainly focuses on evolution. A brief overview of progress around the globe in cavefish research is given, accompanied by an in-depth analysis of the still far-from-complete contributions of Chinese hypogean ichthyofauna studies to this field.