Department of Medical Entomology, Centro Regional de Investigaciones Científicas (CRILAR), Anillaco, La Rioja, Argentina.
Vector Borne Zoonotic Dis. 2011 May;11(5):503-13. doi: 10.1089/vbz.2009.0253. Epub 2010 Oct 6.
Triatoma infestans, one of the main vectors of Trypanosoma cruzi, is strongly associated with rural human ecotopes. Infested peridomestic places could act as a source of house infestation as a result of the movement of vectors among habitats. The quantitative study of phenotypic traits and nutritional variables could be informative about the population structure and the relative mobility of vectors. This is the first approach toward analyzing the phenetic characteristics of T. infestans and the relationship with their potential role to invade and colonize other habitats in the arid Chaco region. This article compares the phenotypic structure of T. infestans populations living in chicken coops and goat corrals, analyzing the geometric morphometry of wings and heads, antennal phenotypes, and the nutritional status of 257 adults and nymphs. The study area remained untreated with insecticides during the 15 years before the present study. The insects collected in peridomestic structures located in two zones 80 km apart exhibited significant differences in their morphotypes, suggesting an environmental effect and/or the absence of individual exchange between zones. The population structure was clear in T. infestans from goat corrals and chicken coops in one zone and less pronounced in the other. These results suggest the existence of a different rate of individual exchange among ecotopes within each zone. Morphometric variables of heads and wings were significantly correlated in insects collected in goat corrals but not in chicken coops, suggesting a habitat effect and supporting the hypothesis of different canalization forces that affect the two organs. The nutritional status of adults indicated a low dispersal probability with zonal differences. This article provides the first combined morphometric analysis of the head of adults and fifth instar nymphs in triatomines and the first combined analysis of head and wing in T. infestans.
布氏田鼠，克氏锥虫的主要载体之一，与农村人类生态位密切相关。受感染的家庭周围环境可能会成为房屋感染的源头，因为媒介在栖息地之间移动。表型特征和营养变量的定量研究可以提供有关种群结构和媒介相对流动性的信息。这是首次分析布氏田鼠的表型特征及其与潜在入侵和定居干旱查科地区其他栖息地的关系。本文比较了生活在鸡舍和山羊围栏中的布氏田鼠种群的表型结构，分析了翅膀和头部的几何形态、触角表型以及 257 只成虫和若虫的营养状况。在本研究之前的 15 年中，研究区域未使用杀虫剂处理。在相距 80 公里的两个区域中收集的生活在家庭周围结构中的昆虫在形态上存在显著差异，这表明存在环境影响和/或两个区域之间个体交换的缺失。一个区域中，山羊围栏和鸡舍中的 T. infestans 种群结构清晰，而另一个区域则不明显。这些结果表明，每个区域内的生态位之间存在不同的个体交换率。在山羊围栏中收集的昆虫中，头部和翅膀的形态变量存在显著相关性，但在鸡舍中则没有，这表明存在栖息地影响，并支持了影响两个器官的不同 canalization 力量的假设。成虫的营养状况表明，个体扩散的可能性较低，且存在区域差异。本文首次对成年三氯甲烷的头部和第五龄若虫进行了综合形态分析，首次对 T. infestans 的头部和翅膀进行了综合分析。
