ITALIAN MARINE GASTROTRICHA - V - 4 NEW AND ONE REDESCRIBED SPECIES OF MACRODASYIDA IN THE DACTYLOPODOLIDAE AND THAUMASTODERMATIDAE

Four species new to science are described and figured from the Italian coastline of the Mediterranean Sea and its adjacent waters: the Medit erranean Dactylopodola mesotyphle n. sp. in the family Dactylopodolida e, a neotenous sibling species of the more geographically ubiquitous D . typhle Remane, 1927, is differentiated from the latter both morpholo gically and biogeographically. Of three species of Tetranchyroderma: T . aphenothigmum n. sp., T. psilotopum n. sp., and T. symphorochetum n. sp. in the family Thaumastodermatidae, the first and third have a com plete dorsal covering of tetrancres, while the second has an incomplet e covering of pentancres. The species Dendrodasys affinis Wilke, 1954 in the family Dactylopodolidae is redescribed, and figured for the fir st time, from specimens collected in littoral and shallow sublittoral sediments near Naples.