ABSTRACT

Studying species with wide geographical distributions allows the evaluation of the effects of environmental variation and phylogenetic constraints on the ecology of these organisms. The snake Tantilla melanocephala is widely distributed across South America in different environments (Amazonia, Atlantic Forest, Cerrado, Caatinga, and Chaco). We compared the morphology, diet, and reproduction of T. melanocephala inhabiting the northeastern Brazil in Atlantic Forest and Caatinga. In total, 161 individuals were collected from the Atlantic Forest and 88 were collected from Caatinga, and all had similar morphological and ecological traits. There was no sexual dimorphism within the biomes, and no morphological differences between individuals from both biomes. The species fed mainly on chilopods, and there were a few differences in the centipede species consumed in each biome. The volume of consumed prey did not differ between biomes, and clutch size was also similar (1–2 eggs), with differences during the egg-laying period reflecting environmental differences. The species has a continuous reproductive cycle in the Atlantic Forest and a seasonal reproductive cycle in Caatinga. Similarities in the morphology and ecology of T. melanocephala in the Atlantic Forest and Caatinga suggests that the species exhibits a high degree of phylogenetic conservatism.

摘要

研究具有广泛地理分布的物种可以评估环境变化和系统发育限制对这些生物生态学的影响。蛇Tantilla melanocephala广泛分布于南美洲的不同环境（亚马逊流域、大西洋森林、塞拉多、卡廷加和查科）。我们比较了T. melanocephala的形态、饮食和繁殖栖息于巴西东北部的大西洋森林和卡廷加。总共从大西洋森林收集了 161 个个体，从卡廷加收集了 88 个个体，它们都具有相似的形态和生态特征。生物群落内没有性别二态性，两个生物群落的个体之间也没有形态差异。该物种主要以足足类动物为食，并且在每个生物群落中消耗的蜈蚣物种存在一些差异。不同生物群落之间消耗的猎物数量没有差异，离合器大小也相似（1-2 个鸡蛋），产卵期间的差异反映了环境差异。该物种在大西洋森林有一个连续的繁殖周期，在卡廷加有一个季节性的繁殖周期。形态学和生态学的相似性大西洋森林和卡廷加的T. melanocephala表明该物种表现出高度的系统发育保守性。