Data from: Forest snail faunas from Transylvania (Romania), and their relationship to the faunas of Central and Northern Europe

Forty-three forest sites in seven sampling areas in mountainous parts of Transylvania were sampled to obtain inventories of their snail faunas, and to make comparisons between these and the faunas of similar sites further north along the Carpathian chain. Sampling areas ran from close to the Ukrainian border in the north to Retezat in the south-west. Altogether, 83 species were found, and between 19 and 40 species at individual sites. Sites within the same sampling area had more species in common than in among-area comparisons, but differences between areas did not relate to distance between them. Such differences appeared to relate more to ecological factors than to geography. Faunas of all areas were very similar to those recorded from the Polish and Ukrainian Carpathians; distance from these northern faunas had little effect on similarity. More broadly, the fauna of these forests shows much greater affinity to those of countries to the north than to those of countries to the south. Despite the survival of forests through the last glacial period of the Pleistocene, and the greater proximity to potential Mediterranean refugia, these faunas appear to be mainly a subset of those found further north. They represent a rather small proportion of the known Romanian fauna, in which there are many endemics restricted to other habitats.

我们对特兰西瓦尼亚山区的7个采样区域内的43处森林样地开展了系统采样，以获取其蜗牛类群区系（snail faunas）名录，并与喀尔巴阡山脉沿线更北部的同类样地的动物区系开展对比。采样区域的分布范围北至接近乌克兰边境处，西南延伸至雷泰扎特山。本次采样共记录到83个蜗牛物种，单处样地的物种丰度介于19至40种之间。同一采样区域内的样地间共有物种数显著多于不同区域样地间的共有物种数，但区域间的物种组成差异与样地间的地理距离并无关联，此类差异更多由生态因子驱动，而非地理因素。所有采样区域的蜗牛区系与波兰、乌克兰喀尔巴阡山区记录的区系极为相似；与这些北部区系的空间距离对区系相似性的影响微乎其微。从更宏观的尺度来看，这些森林的蜗牛区系与北部国家的区系亲缘性远高于其与南部国家的区系。尽管这些森林在更新世末次冰期得以存续，且更接近潜在的地中海避难所，但这些区系本质上仍主要是北部区域所记录区系的一个子集。它们在已知的罗马尼亚陆生软体动物区系中占比极小，而罗马尼亚区系中存在大量局限于其他生境的特有物种。