Programa Doctorado Ciencias Aplicadas, Universidad de Antofagasta, Antofagasta, Chile.
Instituto Milenio de Oceanografía, Universidad de Concepción, Concepción, Chile.
Parasit Vectors. 2019 Oct 30;12(1):512. doi: 10.1186/s13071-019-3756-5.
Parasites of deep-sea fishes from the South-East Pacific (SPO) are poorly known. Of c.1030 species of fish found in this area, 100-150 inhabit the deep-sea (deeper than 200 m). Only six articles concerning metazoan parasites of fish from deep-waters of SOP are known, and nine monogenean species have been reported. Currently, ten species are known in Acanthocotyle Monticelli, 1888 (Monogenea) and when stated, all of them are found in shallow waters (10-100 m). Acanthocotyle gurgesiella Ñacari, Sepulveda, Escribano & Oliva, 2018 is the only known species parasitizing deep-sea skates (350-450 m) in the SPO. The aim of this study was the description of two new species of Acanthocotyle from two Rajiformes.
In September 2017, we examined specimens of two species of deep-sea skates (Rajiformes), Amblyraja frerichsi (Krefft) and Bathyraja peruana McEachran & Myyake, caught at c.1500 m depth off Tocopilla, northern Chile, as a by-catch of the Patagonian tooth fish Dissostichus eleginoides Smitt fishery. Specimens of Acanthocotyle were collected from the skin of the skates. Morphometric (including multivariate analysis of proportional measurements, standardized by total length), morphological and molecular analyses (LSU rRNA and cox1 genes) were performed in order to identify the collected specimens.
The three approaches used in this study strongly suggest the presence of two new species in the genus Acanthocotyle: Acanthocotyle imo n. sp. and Acanthocotyle atacamensis n. sp. parasitizing the skin of the thickbody skate Amblyraja frerichsi and the Peruvian skate Bathyraja peruana, respectively. The main morphological differences from the closely related species Acanthocotyle verrilli Goto, 1899 include the number of radial rows of sclerites, the non-discrete vitelline follicles and the number of testes.
The two species of monogeneans described here are the only recorded parasites from their respective host species in the SPO. Assessing host specificity for members of Acanthocotyle requires clarifying the systematics of Rajiformes.
东南太平洋深海鱼类的寄生虫知之甚少。在该地区发现的约 1030 种鱼类中，有 100-150 种栖息在深海（水深超过 200 米）。已知东南太平洋深海水域鱼类的后生动物寄生虫只有 6 篇文章，报道了 9 种单殖吸虫。目前，有 10 种被认为是 Acanthocotyle Monticelli，1888（单殖吸虫），并且当提到它们时，所有这些寄生虫都存在于浅水区（10-100 米）。Acanthocotyle gurgesiella Ñacari、Sepulveda、Escribano 和 Oliva，2018 是唯一已知寄生在东南太平洋深海鳐鱼（350-450 米）中的物种。本研究的目的是描述来自两种鳐形目鱼类的两种新的 Acanthocotyle 物种。
2017 年 9 月，我们检查了两种深海鳐鱼（鳐形目），即 Amblyraja frerichsi（Krefft）和 Bathyraja peruana McEachran 和 Myyake，的标本，这些标本是在智利北部托科皮亚附近 1500 米深处作为南极牙鱼 Dissostichus eleginoides Smitt 渔业的副渔获物捕获的。从鳐鱼的皮肤中采集 Acanthocotyle 标本。为了鉴定采集到的标本，进行了形态测量学（包括通过总长度标准化的比例测量的多元分析）、形态学和分子分析（LSU rRNA 和 cox1 基因）。
本研究中使用的三种方法强烈表明，在 Acanthocotyle 属中存在两种新物种：寄生在厚体鳐鱼 Amblyraja frerichsi 皮肤中的 Acanthocotyle imo n. sp. 和寄生在秘鲁鳐鱼 Bathyraja peruana 皮肤中的 Acanthocotyle atacamensis n. sp.。与密切相关的物种 Acanthocotyle verrilli Goto，1899 相比，主要的形态差异包括鳞片的辐射行数、不离散的卵黄滤泡和睾丸数。
这里描述的两种单殖吸虫是东南太平洋记录的仅有的来自各自宿主物种的寄生虫。评估 Acanthocotyle 成员的宿主特异性需要澄清鳐形目动物的系统发育。
