Early development of the endemic dace Telestes karsticus is described in a Dinaric karst stream in Croatia. Larvae were acquired from successful rearing in an aquarium. Basic morphometric and meristic measures of larvae were taken during 55 days of observation. The mean total length of larvae at the time of hatching was 6.45 mm. The yolk sac was completely absorbed in all larvae by day 9 post‐hatching (PH), when the mouth also opened and independent feeding and intestinal function were observed. Flexion of the urostyle was completed between days 12–16 PH. The caudal fin became completely forked on day 23 PH. Formation of fin rays was complete on day 48 PH when fish fully resembled juvenile specimens. The number of soft ray fins corresponds to the adult. Understanding the early development is particularly valuable in assessing environmental impacts and recovering of this endangered species and it is essential for effective monitoring and its conservation. This is the first report of the early development for the endemic Telestes karsticus, pointing out the importance of the obtained results for the effective conservation of the species.

中文翻译：

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在克罗地亚的迪纳里克喀斯特地貌流中特有的daTeeles karsticus（Leuciscidae，Cypriniformes）的早期发育

地方性daTeeles karsticus的早期发育在克罗地亚的Dinaric岩溶流中进行了描述。幼虫是通过在水族馆成功饲养而获得的。在观察的55天中，对幼虫进行了基本的形态计量和综合测量。孵化时幼虫的平均总长度为6.45 mm。孵化后第9天（PH），卵黄囊被所有幼虫完全吸收，此时嘴也张开，观察到独立的进食和肠道功能。尿样的弯曲在PH的第12-16天之间完成。尾鳍在PH第23天完全分叉。当鱼完全类似于幼体标本时，在第48天鱼翅的形成就完成了。柔鳍的数量与成年人相对应。了解早期发展对于评估环境影响和恢复该濒危物种的价值尤其重要，对于有效监控和保护其至关重要。这是地方病早期发展的第一份报告Telestes karsticus，指出了获得的结果对于有效保护该物种的重要性。