Gurgel-Gonçalves R, Ferreira J B C, Rosa A F, Bar M E, Galvão C
Laboratório de Parasitologia Médica e Biologia de Vetores, Faculdade de Medicina, Área de Patologia, Universidade de Brasília, Asa Norte, Distrito Federal, Brazil.
Med Vet Entomol. 2011 Mar;25(1):84-93. doi: 10.1111/j.1365-2915.2010.00920.x. Epub 2010 Nov 15.
Identifying morphologically similar triatomine species is key to Chagas' disease vector control and surveillance, but remains challenging when only qualitative phenotypic data are available. We investigated whether morphometric and ecological variation can provide additional criteria for species delimitation by combining geometric morphometrics and ecological niche modelling to characterize two near-sibling triatomine species, Triatoma sordida and Triatoma garciabesi (Reduviidae: Triatominae). We analysed size and shape variation in 231 wings and 123 heads from one T. garciabesi and three T. sordida populations. Predicted distribution maps (21 climatic variables, 324 vector occurrence points) were produced using the Maxent method. Multivariate analyses summarized morphological and ecological variation. Wings and heads of T. sordida were significantly larger and more elongated than those of T. garciabesi. Discriminant analyses separated the species, with a partial overlap between Argentinean populations. The predicted distribution of T. garciabesi included northwest Argentina (mainly arid Chaco), whereas that of T. sordida included northeast Argentina (humid Chaco) and the Brazilian Cerrado and Caatinga ecoregions. Clear ecological niche differences were observed, with T. garciabesi occupying colder and drier areas than T. sordida. Our results show how morphometric variation and niche divergence can be used to enhance operational criteria for the delimitation of phenotypically similar triatomine species.
识别形态相似的锥蝽物种是恰加斯病病媒控制和监测的关键，但在仅有定性表型数据可用时仍具有挑战性。我们通过结合几何形态计量学和生态位建模来研究形态计量和生态变异是否能为物种界定提供额外标准，以表征两种近缘锥蝽物种，即污色锥蝽和加西亚锥蝽（猎蝽科：锥蝽亚科）。我们分析了来自一个加西亚锥蝽种群和三个污色锥蝽种群的231个翅膀和123个头的大小和形状变异。使用最大熵方法生成了预测分布图（21个气候变量，324个病媒出现点）。多变量分析总结了形态和生态变异。污色锥蝽的翅膀和头部明显比加西亚锥蝽的更大且更细长。判别分析将这两个物种区分开来，阿根廷种群之间存在部分重叠。加西亚锥蝽的预测分布包括阿根廷西北部（主要是干旱的查科地区），而污色锥蝽的预测分布包括阿根廷东北部（湿润的查科地区）以及巴西的塞拉多和卡廷加生态区。观察到明显的生态位差异，加西亚锥蝽占据的区域比污色锥蝽更寒冷、更干燥。我们的结果表明形态计量变异和生态位分化可如何用于加强对形态相似的锥蝽物种进行界定的操作标准。
