Instituto Nacional de Tecnología Agropecuaria, Estación Experimental Agropecuaria Rafaela, and Consejo Nacional de Investigaciones Científicas y Técnicas, CC 22, CP 2300, Rafaela, Santa Fe, Argentina.
Parasitology Unit, University of Hohenheim, Emil-Wolff-Straße 34, 70593, Stuttgart, Germany.
Ticks Tick Borne Dis. 2018 Jul;9(5):1264-1274. doi: 10.1016/j.ttbdis.2018.04.009. Epub 2018 Apr 27.
The aim of this work was to generate knowledge on ecological aspects of Amblyomma sculptum in Argentina, such as seasonal dynamics, geographical range size, hosts, genetic diversity and phylogeography. Adult and immature A. sculptum ticks were collected in different localities of Argentina to know the geographical range size and hosts. The genetic diversity of this tick was studied through analyses of 16S rDNA sequences. To describe the seasonal dynamics, free-living ticks were monthly collected from October 2013 to October 2015. A. sculptum shows a marked ecological preference for Chaco Húmedo eco-region and "Albardones" forest of the great rivers in the wetlands in the Chaco Biogeographical Province, and for Selvas Pedemontanas and Selva Montana in the Yungas Biogeographical Province. This species has low host specificity, and it has large wild and domestic mammals as principal hosts to both immature and adult stages. Amblyomma sculptum is characterized by a one-year life cycle. Larvae peak in early winter, nymphs peaked during mid-spring, and adults during late summer and mid-summer. The genetic divergence was low and the total genetic variability was attributable to differences among populations. This fact could be associated to stochastics process linked to micro-habitat variations that could produce a partial restriction to gene flow among populations. The geographic regions do not contribute much to explain the A. sculptum population genetic structure, with an ancestral haplotype present in most populations, which gives rise to the rest of the haplotypes denoting a rapid population expansion.
本研究旨在探讨阿根廷纹皮赤蛉的生态方面的知识，包括季节性动态、地理范围大小、宿主、遗传多样性和系统地理学。在阿根廷的不同地区采集成蜱和若蜱来了解地理范围大小和宿主。通过 16S rDNA 序列分析研究了该蜱的遗传多样性。为了描述季节性动态，从 2013 年 10 月到 2015 年 10 月，每月从自由生活的蜱中采集样本。纹皮赤蛉明显偏好查科湿地的查科湿润生态区和大河流的“阿尔瓦多内斯”森林，以及查科生物地理区的佩德蒙特纳萨斯和蒙塔内萨斯以及 Yungas 生物地理区的塞拉瓦。该物种宿主特异性低，幼蜱和成蜱的主要宿主都是大型野生和家养哺乳动物。纹皮赤蛉的生命周期为一年。幼虫在初冬达到高峰，若虫在仲春达到高峰，成虫在夏末和仲夏达到高峰。遗传分化程度较低，总遗传变异性归因于种群间的差异。这一事实可能与与微生境变化相关的随机过程有关，这种变化可能会对种群间的基因流产生局部限制。地理区域对解释纹皮赤蛉种群遗传结构的贡献不大，大多数种群都存在一个祖先单倍型，其余的单倍型则表示种群的快速扩张。
