First record of Esox cisalpinus (Teleostea: Esocidae) in Sardinia with insight on its mitochondrial DNA genetic variability

Esox cisalpinus (Teleostea: Esocidae) (syn. Esox flaviae) is an Italian freshwater autochthonous fish, whose originary range is limited to the Northern and Central Italy. However, this species has historically been introduced in several areas of Southern Italy, mainly for recreational purposes. In this paper we report the first record of E. cisalpinus on the Sardinia island (Western Mediterranean, Italy), where the species has been recently introduced at least in one lake. The species identification and the population dynamics analysis were performed using mitochondrial markers. The level of genetic variability, compared to those of other peninsular populations of E. cisalpinus, was surprisingly high, and several never-before-described haplotypes were found. A total of 10 mtDNA haplotypes were found. Demographic analysis is suggestive of a population expansion. We hypothesise that E. cisalpinus has been introduced in the Sardinian lake by the releasing of a conspicuous number of individuals. Given the conservational and recreational interest that E. cisalpinus arouses, it would be advisable that Sardinian government focuses in the near future also on management measures of its Sardinian population.意大利梭鲈（Esox cisalpinus，硬骨鱼纲Teleostei：狗鱼科Esocidae，异名Esox flaviae）是意大利本土淡水原生物种，其原生分布范围仅局限于意大利北部与中部。历史上，该物种曾被引入意大利南部多个区域，主要用于休闲垂钓活动。本研究报道了意大利梭鲈在撒丁岛（意大利西地中海海域）的首次发现记录——该物种近期已至少在当地一处湖泊中被引入。研究采用线粒体分子标记完成了物种鉴定与种群动态分析，结果显示：与该物种其他半岛种群相比，其遗传变异水平异常偏高，且发现了多个此前未被正式描述的单倍型（haplotype）。本次研究总计检出10个线粒体DNA单倍型。种群统计分析结果表明该种群正处于扩张阶段。研究推测，该物种是通过批量放生大量个体的方式被引入撒丁岛的该湖泊中。鉴于意大利梭鲈兼具保护研究价值与休闲垂钓价值，撒丁岛政府应在未来尽快针对其撒丁岛种群制定专项管理措施。