Posgrado en Ciencias Biológicas, Instituto de Biología, Universidad Nacional Autónoma de México, s/n, Ciudad Universitaria, Coyoacán, Ciudad de México C.P. 04510, Mexico; Instituto de Biología, Universidad Nacional Autónoma de México, Tercer circuito exterior s/n, Ciudad Universitaria, Coyoacán, Ciudad de México C.P. 04510, Mexico.
Instituto de Biología, Universidad Nacional Autónoma de México, Tercer circuito exterior s/n, Ciudad Universitaria, Coyoacán, Ciudad de México C.P. 04510, Mexico.
Parasitol Int. 2022 Aug;89:102578. doi: 10.1016/j.parint.2022.102578. Epub 2022 Mar 17.
Haematoloechus comprises a species-rich genus of trematodes commonly found in the lungs of amphibians across the globe. Of the approximately 70 species reported worldwide, Mexico stands out as a biodiversity hot spot for the genus, with 16 species described. In Los Tuxtlas tropical rainforest, in south-eastern Mexico, three species have been reported, two of them endemic of the frog species occurring in the area. Here, we added the record of a fourth species in the area, and partially elucidated the life cycle of these species using DNA sequence data from the 28S rRNA and the COI genes. Frogs, and a diverse array of species of aquatic insects were sampled in two lakes within the tropical rain forest. Adults and metacercariae of Haematoloechus were obtained. Both developmental stages were linked molecularly contributing to our understanding of their transmission pathways, and probable host-specificity patterns. Each of the four species of Haematoloechus were sampled in a particular species of anisopteran odonate, and therefore were considered as specialists towards their second intermediate host. We validated the presence of H. complexus in the region of Los Tuxtlas because their metacercariae, sampled in the anisopteran dragongly Agriogomphus tumens, matched with sequences of H. complexus from Nebraska and Illinois in USA. We further described the ultrastructure of the tegument of three of the four species of Haematoloechus, sampled from their definitive host (Rana vaillanti, Rana berlandieri), to contribute with characters that can be reliable for species delimitation of the genus.
肝片形吸虫属是一种种类丰富的吸虫，通常存在于全球范围内的两栖动物肺部。在全球约 70 种已报告的物种中，墨西哥是该属的生物多样性热点地区，有 16 种被描述。在墨西哥东南部的洛斯图尔塔斯热带雨林中，已经报告了三种物种，其中两种是该地区特有蛙种的内寄生物。在这里，我们在该地区记录了第四种物种，并使用来自 28S rRNA 和 COI 基因的 DNA 序列数据部分阐明了这些物种的生命周期。在热带雨林中的两个湖泊中，对青蛙和各种水生昆虫进行了采样。获得了肝片形吸虫的成虫和后尾蚴。这两个发育阶段都通过分子手段联系起来，有助于我们了解它们的传播途径和可能的宿主特异性模式。肝片形吸虫的四个物种都在一种特定的蜻蜓目昆虫中进行了采样，因此被认为是它们第二中间宿主的专性寄生物。我们验证了肝片形吸虫复合体在洛斯图尔塔斯地区的存在，因为在蜻蜓目 Dragongly Agriogomphus tumens 中采样的后尾蚴与来自美国内布拉斯加州和伊利诺伊州的肝片形吸虫复合体序列相匹配。我们进一步描述了从其终末宿主（Rana vaillanti、Rana berlandieri）中采样的肝片形吸虫属的四个物种中的三个的表皮超微结构，为该属的物种划界提供了可靠的特征。
