ABSTRACT

The Central American Isthmus has had profound effects on the evolution and distribution of larger marine organisms, but the impacts on meiobenthic animals have received little attention. Tardigrades are microscopic metazoan lobopodians that are ubiquitous in benthic communities worldwide, but little is known about marine tardigrades in Central America. Only two marine tardigrades have been identified to species level in all of Central America, and these came from a single sample of barnacles from El Salvador collected in 1953. Additionally, multiple haplotypes of Echiniscoides were reported from Costa Rica and Panama, but species names were not assigned. Here we report an extensive survey of both intertidal and subtidal marine tardigrades from both the Caribbean and Pacific coasts of Costa Rica. We found 701 individuals in 65 samples. There was a total of 19 taxa, including seven species with a sufficient quality and quantity of specimens to describe here as new to science. The new species are Archechiniscus murilloi sp. nov., Batillipes homocercus sp. nov., Batillipes ichthyocercus sp. nov., Echiniscoides costaricensis sp. nov., Echiniscoides ritavargasae sp. nov., Styraconyx vargasi sp. nov. and Tanarctus breedyae sp. nov. Ten taxa were found only in the Caribbean, six were found only in the Pacific, and three were found on both coasts. We discuss the three species with trans-isthmus distributions and note two additional candidate geminate species pairs that warrant further investigation.

摘要

中美洲地峡对大型海洋生物的进化和分布产生了深远的影响，但对小型底栖动物的影响却很少受到关注。缓步动物是微小的后生动物叶足类动物，在世界各地的底栖群落中无处不在，但对中美洲的海洋缓步动物知之甚少。在整个中美洲，只有两种海洋缓步动物被鉴定到物种水平，它们来自于 1953 年从萨尔瓦多收集的单一藤壶样本。此外，Echiniscoides 的多个单倍型来自哥斯达黎加和巴拿马的报告，但没有指定物种名称。在这里，我们报告了对哥斯达黎加加勒比海和太平洋沿岸的潮间带和潮下带海洋缓步动物的广泛调查。我们在 65 个样本中发现了 701 个个体。共有 19 个分类群，其中包括 7 个物种，其标本的质量和数量足以在此处将其描述为科学上的新物种。新种是Archechiniscus murilloi sp。十一月，Batillipes homocercus sp. 十一月，Batillipes ichthyocercus sp. 十一月，Echiniscoides costaricensis sp. 十一月，Echiniscoides ritavargasae sp. 十一月，Styraconyx vargasi sp. 十一月 和牛膝草sp. 十一月 仅在加勒比海地区发现了 10 个分类群，仅在太平洋地区发现了 6 个分类群，在两个海岸都发现了 3 个。我们讨论了具有跨地峡分布的三个物种，并注意到另外两个值得进一步研究的候选双生物种对。