We describe adult males and females and a nymph belonging to Linguatula serrata in Australia, based on light and scanning electron microscopies. In addition, 18S and Cox1 sequence data have also been provided and were compared with similar sequences in GenBank. Our specimens had identical 18S sequences and limited genetic distance in Cox1 region which fell within the intra-specific range observed for Linguatula spp. suggesting that they all belong to one species. Phylogenetic analyses showed that Australian specimens were grouped with L. serrata in Europe where the species was first found and described. A number of L. serrata from Iran and Bangladesh formed a distinct group. The genetic distance between these Linguatula and Australian/European L. serrata ranged from 0.46% to 2.21% which is larger than the genetic distance observed between L. arctica and Australian/European L. serrata (0.12%) suggesting that they belong to a different species. As pointed out previously by several other authors, L. serrata comprises more than one species and those from the Palearctic region (including Iran and Bangladesh) should not be automatically named L. serrata unless there is enough evidence for the identification. To accurately address the complex taxonomy of Linguatula spp. a detailed morphological and genetic characterisation of numerous developmental stages of the parasite is necessary, to ensure morphological differences are not due to development. This however may not be achievable in the near future due to significant reduction in expertise as well as research funding awarded in this area of research to understand the basics of our planet.

中文翻译：

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澳大利亚舌虫 Linguatula serrata（Pentastomida：Linguatulidae）的特征。


我们根据光学和扫描电子显微镜描述了澳大利亚的成年雄性和雌性以及属于锯齿舌舌虫的若虫。此外，还提供了18S和Cox1序列数据，并与GenBank中的相似序列进行了比较。我们的样本具有相同的 18S 序列，Cox1 区域的遗传距离有限，属于 Linguatula spp 观察到的种内范围内。表明它们都属于一个物种。系统发育分析表明，澳大利亚标本与欧洲的 L. serrata 归为一类，该物种是在欧洲首次发现和描述的。许多来自伊朗和孟加拉国的 L. serrata 形成了一个独特的类群。这些 Linguatula 与澳大利亚/欧洲 L. serrata 之间的遗传距离为 0.46% 至 2.21%，大于 L. arctica 与澳大利亚/欧洲 L. serrata 之间观察到的遗传距离 (0.12%)，表明它们属于不同的物种。物种。正如其他几位作者之前指出的，L. serrata 包含多个物种，来自古北区（包括伊朗和孟加拉国）的物种不应自动命名为 L. serrata，除非有足够的证据进行鉴定。为了准确解决 Linguatula spp 的复杂分类问题。有必要对寄生虫的多个发育阶段进行详细的形态和遗传表征，以确保形态差异不是由于发育造成的。然而，由于该领域为了解地球基础知识而提供的专业知识和研究经费大幅减少，这一目标在不久的将来可能无法实现。