Laboratório de Parasitologia, Departamento de Ciências Biológicas, Universidade Estadual Paulista "Júlio de Mesquita Filho" (UNESP), Faculdade de Ciências Farmacêuticas, Araraquara, São Paulo, Brasil.
Instituto de Biociências, Universidade Estadual Paulista "Júlio de Mesquita Filho", IBB/UNESP, Botucatu, São Paulo, Brasil.
PLoS One. 2021 Oct 15;16(10):e0257992. doi: 10.1371/journal.pone.0257992. eCollection 2021.
Triatomines are hematophagous insects of great epidemiological importance, since they are vectors of the protozoan Trypanosoma cruzi, the etiological agent of Chagas disease. Triatoma brasiliensis complex is a monophyletic group formed by two subspecies and six species: T. b. brasiliensis, T. b. macromelasoma, T. bahiensis, T. juazeirensis, T. lenti, T. melanica, T. petrocchiae and T. sherlocki. The specific status of several species grouped in the T. brasiliensis complex was confirmed from experimental crossing and analysis of reproductive barriers. Thus, we perform interspecific experimental crosses between T. lenti and other species and subspecies of the T. brasiliensis complex and perform morphological analysis of the gonads and cytogenetic analysis in the homeologous chromosomes of the hybrids of first generation (F1). Besides that, we rescue all the literature data associated with the study of reproductive barriers in this monophyletic complex of species and subspecies. For all crosses performed between T. b. brasiliensis, T. b. macromelasoma, T. juazeirensis and T. melanica with T. lenti, interspecific copulas occurred (showing absence of mechanical isolation), hybrids were obtained, none of the male hybrids presented the phenomenon of gonadal dysgenesis and 100% pairing between the chromosomes homeologous of the hybrids was observed. Thus, we demonstrate that there are no pre-zygotic reproductive barriers installed between T. lenti and the species and subspecies of the T. brasiliensis complex. In addition, we demonstrate that the hybrids obtained between these crosses have high genomic compatibility and the absence of gonadal dysgenesis. These results point to reproductive compatibility between T. lenti and species and subspecies of the T. brasiliensis complex (confirming its inclusion in the complex) and lead us to suggest a possible recent diversification of the taxa of this monophyletic group.
锥蝽是具有重要流行病学意义的血吸昆虫，因为它们是原生动物克氏锥虫的传播媒介，克氏锥虫是恰加斯病的病原体。巴西锥蝽复合体是由两个亚种和六个物种组成的单系群：T. b. brasiliensis、T. b. macromelasoma、T. bahiensis、T. juazeirensis、T. lenti、T. melanica、T. petrocchiae 和 T. sherlocki。从实验杂交和生殖障碍分析中证实了几种在巴西锥蝽复合体中分组的物种的特有状态。因此，我们在 T. lenti 和巴西锥蝽复合体的其他物种和亚种之间进行种间实验杂交，并对第一代（F1）杂种的性腺进行形态分析和同源染色体的细胞遗传学分析。此外，我们还抢救了与这个物种和亚种单系复合体的生殖障碍研究相关的所有文献数据。对于 T. b. brasiliensis、T. b. macromelasoma、T. juazeirensis 和 T. melanica 与 T. lenti 之间进行的所有杂交，都发生了种间交配（表明不存在机械隔离），获得了杂种，没有雄性杂种出现性腺发育不良现象，并且观察到杂种同源染色体之间的 100%配对。因此，我们证明了在 T. lenti 和巴西锥蝽复合体的物种和亚种之间不存在合子前生殖障碍。此外，我们证明了这些杂交获得的杂种具有很高的基因组相容性和不存在性腺发育不良。这些结果表明 T. lenti 和巴西锥蝽复合体的物种和亚种之间存在生殖相容性（证实了它包含在复合体中），并促使我们提出这个单系群的分类单元可能存在最近的多样化。
