Laboratório de Biodiversidade Entomológica, Instituto Oswaldo Cruz-Fiocruz, Rio de Janeiro, Brazil.
Acta Trop. 2013 Oct;128(1):162-7. doi: 10.1016/j.actatropica.2013.06.019. Epub 2013 Jul 10.
Phylogenetic approaches based on mitochondrial DNA variation (fragments of Cyt B and 16S ribosomal RNA) have revealed Triatoma sherlocki as the most recent species addition to the Triatoma brasiliensis species complex; a monophyletic group which includes T. brasiliensis, Triatoma melanica, and Triatoma juazeirensis. T. sherlocki is the most differentiated among all species of this complex: it is unable to fly, possesses longer legs than the other members, and has reddish tonality in some parts of its exochorion. We question whether these species are reproductively compatible because of this pronounced morphological differentiation, and therefore, we present a series of cross breeding experiments that test compatibility between T. sherlocki and other members of the T. brasiliensis complex. We extended our analyses to include crosses between T. sherlocki and Triatoma lenti, because the latter has been suggested as a possible member of this complex. T. sherlocki male×T. lenti female pairs failed to produce hybrids. All other crosses of T. sherlocki and members of T. brasiliensis species complex, as well as backcrosses, produced viable offspring through the third generation. This study stresses the importance of searching for the features that may isolate members of the T. brasiliensis species complex.
基于线粒体 DNA 变异（Cyt B 和 16S 核糖体 RNA 片段）的系统发育方法揭示，Triatoma sherlocki 是 Triatoma brasiliensis 种复合物中最近添加的物种；这是一个单系群，包括 T. brasiliensis、Triatoma melanica 和 Triatoma juazeirensis。T. sherlocki 是该复合物中所有物种中分化最大的：它不能飞行，腿比其他成员长，外骨骼的某些部分呈红色调。由于这种明显的形态分化，我们质疑这些物种是否具有生殖兼容性，因此，我们进行了一系列杂交实验，以测试 T. sherlocki 与 T. brasiliensis 复合物的其他成员之间的兼容性。我们将分析扩展到包括 T. sherlocki 和 Triatoma lenti 之间的交叉，因为后者被认为是该复合物的可能成员。T. sherlocki 雄性×T. lenti 雌性对未能产生杂种。T. sherlocki 和 T. brasiliensis 种复合物的所有其他成员的交叉以及回交都通过第三代产生了有活力的后代。这项研究强调了寻找可能隔离 T. brasiliensis 种复合物成员的特征的重要性。
