Arthurius Bunakenensis,a New Tropical Indo-pacific Species Of Endoparasitic Copepods From A Sacoglossan Opisthobranch Host

摘要

Within the framework of our worldwide revision of splanchnotrophid copepod endoparasites we herein describe Arthurius bunakenensis spec, nov., the second species of the previously monotypic genus Arthurius Huys, 2001. During our joint International Bunaken National Park Diving Expedition 2003 we found female and male specimens parasitizing within the sacoglossan Elysia pusilla Bergh, 1872 at Gangga Island, off northern Sulawesi, Indonesia. The parasites are described using Scanning Electron Microscopy (SEM). As in Arthurius elysiae (Jensen, 1990), mandibles and maxillules are absent in both sexes which is diagnostic for the genus. While males are very similar to each other, females of Arthurius bunakenensis n. sp. clearly differ from A. elysiae by the number, shape and position of body processes. An unnamed putative congener described by Risbec (1930) shows similar body processes but was inadequately described for detailed comparison.