Martínez-Aquino Andrés, Vidal-Martínez Víctor M, Ceccarelli F Sara, Méndez Oscar, Soler-Jiménez Lilia C, Aguirre-Macedo M Leopoldina
Facultad de Ciencias, Universidad Autónoma de Baja California, Carretera Transpeninsular 3917, Fraccionamiento Playitas, Ensenada, Baja California 22860, México.
Laboratorio de Patología Acuática, Departamento de Recursos del Mar, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Unidad Mérida, Cordemex, Carretera Antigua a Progreso Km. 6, Mérida, Yucatán 97310, México.
Curr Zool. 2020 Jun;66(3):275-283. doi: 10.1093/cz/zoz045. Epub 2019 Sep 16.
Despite the diversity and ecological importance of cestodes, there is a paucity of studies on their life stages (i.e., complete lists of intermediate, paratenic, and definitive hosts) and genetic variation. For example, in the Gulf of Mexico (GoM) 98 species of cestodes have been reported to date; however, data on their intraspecific genetic variation and population genetic studies are lacking. The trypanorhynch cestode, , is found (among other places) off the American Western Atlantic Coast, including the GoM, and has been reported as an adult from stingrays and from several teleost species in its larval form (as plerocerci). This study represents the first report of 2 previously unregistered definitive hosts for , namely the Atlantic sharpnose shark and the southern stingray . In this work, partial sequences of the 28S (region D1-D2) ribosomal DNA were analyzed to include within an eutetrarhynchoid phylogenetic framework. All individuals (which included plerocerci and adults) were recovered as monophyletic and was identified as the sister species of . Furthermore, population genetic analyses of from the southern GoM were carried out using DNA sequences of the mitochondrial cytochrome c oxidase subunit 1 (COI) gene, which reflected high genetic variation and a lack of genetic structure among the 9 oceanographic sampling sites. Based on these results, is panmictic in the southern GoM. More extensive sampling along the species entire distribution is necessary to make more accurate inferences of population genetics of .
尽管绦虫具有多样性和生态重要性，但对其生活史阶段（即中间宿主、转续宿主和终末宿主的完整列表）和遗传变异的研究却很匮乏。例如，迄今为止，在墨西哥湾已报告有98种绦虫；然而，关于它们种内遗传变异和群体遗传学研究的数据却很缺乏。旋吻绦虫，在美国西大西洋沿岸（包括墨西哥湾）被发现，并且有报告称其成虫寄生于黄貂鱼，幼虫形态（裂头蚴）寄生于几种硬骨鱼。本研究首次报告了该绦虫的2种先前未记录的终末宿主，即大西洋尖吻鲨和南方黄貂鱼。在这项工作中，对28S核糖体DNA（区域D1 - D2）的部分序列进行了分析，以便将该绦虫纳入真四吻虫类系统发育框架。所有个体（包括裂头蚴和成虫）均被归为单系类群，并且该绦虫被鉴定为某物种的姐妹种。此外，利用线粒体细胞色素c氧化酶亚基1（COI）基因的DNA序列对墨西哥湾南部的该绦虫进行了群体遗传学分析，结果显示在9个海洋学采样点中该绦虫具有高遗传变异且缺乏遗传结构。基于这些结果，该绦虫在墨西哥湾南部是随机交配的。有必要在该物种的整个分布范围内进行更广泛的采样，以便对其群体遗传学做出更准确的推断。
