Cuticular structures and epidermal glands of Echinoderes cantabricus and E-hispanicus (Kinorhyncha, Cydorhagida) with special reference to their taxonomic value

The body wall of two species of kinorhynchs, Echinoderes cantabricus and E. hispanicus, was examined with transmission and scanning electron microscop y, to determine accurately the nature, arrangement, and consistency of char acters used for taxonomic purposes. Structural details of cuticular hairs, pectinate fringes, spines, tubules, and different cuticular scars are descr ibed and discussed. Two kinds of epidermal glands, types 1 and 2, are chara cterized according to the nature of their secretory products, their exact l ocation and distribution in the trunk segments, and their possible value as taxonomic characters. The generally assumed function of tubules for the re lease of secretory product is analyzed and finally rejected in light of the different distribution of tubules and glands along the trunk and because o f the absence of a clear anatomic relation between both structures. The cut icular features studied can be useful for taxonomic purposes because of the ir consistency, but some of them are difficult to access and evaluate and t herefore must be used with caution. (C) 2000 Wiley-Liss, Inc.