PDF(Pubmed)
Abstract：
The Sardinian grass snake, Natrix helvetica cetti, is an endangered endemic snake subspecies with a restricted and highly fragmented geographic distribution. Information on its ecology and detailed geographic distribution are scarce and may negatively impact on its conservation status. Therefore, a literature review on its taxonomy, morphology, ecology, and conservation is presented here. Moreover, field records from the authors, citizen science and the existing literature provide an updated geographic distribution highlighting its presence within 13 new and 7 historic 10 × 10 km cells. Bioclimatic niche modelling was then applied to explore patterns of habitat suitability and phenotypic variation within N. h. cetti. The geographic distribution of the species was found to be positively correlated with altitude and precipitation values, whereas temperature showed a negative correlation. Taken together, these outcomes may explain the snake\'s presence, particularly in eastern Sardinia. In addition, analysis of distribution overlap with the competing viperine snake (N. maura) and the urodeles as possible overlooked trophic resources (Speleomantes spp. and Euproctus platycephalus) showed overlaps of 66% and 79%, respectively. Finally, geographical or bioclimatic correlations did not explain phenotypic variation patterns observed in this highly polymorphic taxon. Perspectives on future research to investigate N. h. cetti\'s decline and support effective conservation measures are discussed.
摘要：
撒丁岛草蛇,NatrixHelveticaCetti,是濒危的特有蛇亚种，地理分布受限且高度分散。有关其生态和详细地理分布的信息很少，可能会对其保护状况产生负面影响。因此,关于其分类法的文献综述，形态学,生态学,这里介绍了保护。此外，作者的现场记录，公民科学和现有文献提供了最新的地理分布，突出了它在13个新的和7个具有历史意义的10×10km单元格中的存在。然后应用生物气候生态位模型来探索N.h.cetti内的栖息地适宜性和表型变异模式。发现该物种的地理分布与海拔和降水值呈正相关，而温度呈负相关。一起来看,这些结果可以解释蛇的存在，尤其是在撒丁岛东部。此外,与竞争毒蛇的分布重叠分析(N.maura）和尾随动物可能被忽视的营养资源（Speleomantesspp。和桔梗)显示66%和79%的重叠，分别。最后,地理或生物气候相关性不能解释在这种高度多态分类单元中观察到的表型变异模式。对N.h.cetti的衰落和支持有效保护措施的未来研究前景进行了讨论。
