ABSTRACT Many species of microscopic invertebrates, such as tardigrades or rotifers, have been traditionally regarded as cosmopolitan. This conviction was based on classical taxonomic observations of very similar phenotypes across the globe and hypothetical abilities of micrometazoans for large-scale dispersal with air and water currents. However, several recent studies showed that micrometazoan species may have restricted geographic ranges, suggesting that microscopic size is not the only determinant of dispersal. Here, we describe the first Australasian record of Echiniscus testudo, a heterotardigrade originally described from the Holarctic. Morphological and genetic analyses gave congruent conclusions and confirmed that European and New Zealand populations represent a single species. Importantly, however, without broader sampling in primeval localities, it is not possible to test whether the New Zealand record of E. testudo is a result of natural dispersal or whether the species was brought to Australasia by humans.

中文翻译：

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新西兰的 Echiniscus testudo（Doyère，1840 年）：人为传播或“万物无处不在”假说的证据？

摘要 许多微观无脊椎动物，如缓步动物或轮虫，传统上被认为是世界性的。这一信念是基于对全球非常相似表型的经典分类观察以及微后生动物在空气和水流中大规模传播的假设能力。然而，最近的几项研究表明，微后生动物物种的地理范围可能受到限制，这表明微观尺寸并不是扩散的唯一决定因素。在这里，我们描述了 Echiniscus testudo 的第一个澳大利亚记录，Echiniscus testudo 是一种最初描述于 Holarctic 的异缓步动物。形态学和遗传分析得出了一致的结论，并证实欧洲和新西兰种群代表一个物种。然而，重要的是，