Two new species of the problematic harpacticoid genus Itunella (Copepoda, Canthocamptidae)

Abstract

The genus Itunella Brady, 1896 has a troubled taxonomic past, partly because of paucity of its members, but mostly because of inadequate research. A lack of detail in species descriptions and redescriptions, absence of alternative methods for testing species hypotheses, combined with a notion that most marine and estuarine animals have wide distributions and enormous intraspecific variability, all resulted in blurring of some interspecific boundaries, synonymizing without examination of the type material, and founding species diagnoses on dubious characters. Itunella yeondeokensis sp. nov. is described here in great detail from a small sandy beach on the east coast of Korea. It differs from all reported and illustrated congeners by an extremely long inner apical seta on the third exopodal segment of second to fourth swimming legs. This is the second member of this genus from Korea, the first one being described from three estuaries also on the east coast. All other congeners are European species. An overview of all published species and records of this genus is provided, as well as a dichotomous key to valid species to aid in their identification. Itunella kieferi sp. nov. is a new name for a single female from Germany, previously reported as a member of a widely distributed and polymorphic species. The genus Itunella Brady, 1896 has a troubled taxonomic past, partly because of paucity of its members, but mostly because of inadequate research. A lack of detail in species descriptions and redescriptions, absence of alternative methods for testing species hypotheses, combined with a notion that most marine and estuarine animals have wide distributions and enormous intraspecific variability, all resulted in blurring of some interspecific boundaries, synonymizing without examination of the type material, and founding species diagnoses on dubious characters. Itunella yeondeokensis sp. nov. is described here in great detail from a small sandy beach on the east coast of Korea. It differs from all reported and illustrated congeners by an extremely long inner apical seta on the third exopodal segment of second to fourth swimming legs. This is the second member of this genus from Korea, the first one being described from three estuaries also on the east coast. All other congeners are European species. An overview of all published species and records of this genus is provided, as well as a dichotomous key to valid species to aid in their identification. Itunella kieferi sp. nov. is a new name for a single female from Germany, previously reported as a member of a widely distributed and polymorphic species.