Testa J M, Montoya-Lerma J, Cadena H, Oviedo M, Ready P D
Department of Entomology, The Natural History Museum, Cromwell Road, London SW7 5BD, UK.
Acta Trop. 2002 Dec;84(3):205-18. doi: 10.1016/s0001-706x(02)00187-0.
The identity of the sandfly vectors of Leishmania braziliensis in Valle del Cauca Department, Colombia, was originally given as Lutzomyia townsendi, but then changed to L. youngi, another member of the L. townsendi series (Verrucarum group) with isomorphic females. To identify members of this series in Valle del Cauca, we analyzed the nuclear gene elongation factor-alpha (EF-alpha) and the mitochondrial gene cytochrome b (Cyt b). DNA sequences from the L. verrucarum series (L. columbiana, L. evansi and L. ovallesi) were used as outgroups. Flies from two locations on the western cordillera of the Andes were identified as L. townsendi s.s., according to male morphology and distinctive gene lineages. In the third location, on the central cordillera of the Andes, most specimens were identified as belonging to a geographical population of L. youngi, according to male morphology, an EF-alpha lineage shared with L. youngi from the Venezuelan-type locality, and a distinctive Cyt b sub-lineage. All other specimens were identified as L. youngi with the introgressed Cyt b sequences of L. townsendi. Such interspecific introgression implies that vectorial traits and ecological associations may no longer be viewed as fixed properties of different morphospecies.
在哥伦比亚考卡山谷省，巴西利什曼原虫的白蛉传播媒介最初被认定为汤森卢蛉，但后来改为扬氏卢蛉，它是汤森卢蛉系列（疣螨组）的另一个成员，其雌虫形态相同。为了鉴定考卡山谷省该系列的成员，我们分析了核基因延伸因子α（EF-α）和线粒体基因细胞色素b（Cyt b）。来自疣螨卢蛉系列（哥伦比亚卢蛉、埃氏卢蛉和卵形卢蛉）的DNA序列用作外群。根据雄虫形态和独特的基因谱系，来自安第斯山脉西部科迪勒拉两个地点的苍蝇被鉴定为狭义汤森卢蛉。在第三个地点，即安第斯山脉中部科迪勒拉，根据雄虫形态、与来自委内瑞拉类型地点的扬氏卢蛉共享的EF-α谱系以及独特的Cyt b亚谱系，大多数标本被鉴定为属于扬氏卢蛉的一个地理种群。所有其他标本被鉴定为具有汤森卢蛉渗入Cyt b序列的扬氏卢蛉。这种种间渗入意味着传播特性和生态关联可能不再被视为不同形态物种的固定属性。
