Some remarks on the taxonomy of Antarctic Leuconidae (Cumacea: Crustacea) with a description of a new species Leucon intermedius n. sp.

Abstract

The newly described species Leucon intermedius n. sp. differs from, other known Leucon species by an inconspicuous antennal notch and the presence of only a few teeth at the dorsomedian crest. The species most similar to Leucon intermedius are L. septemdentatus and L. inexcavatus from the Antarctic/Subantarctic Ocean. A Table is given to allow direct comparison of the characteristics of all Leucon species known from the Antarctic/Subantarctic Ocean. Forty-one specimens of Leucon intermedius n. sp. were collected at depths ranging from 109 to 791 m in the vicinity of the Amery Depression (Indian Sector) and near King George Island (South Shetland Islands). Problems in distinguishing the Antarctic/Subantarctic species of the genus Eudorella are discussed. The shape of the antennal notch is suggested as a better characteristic to distinguish the Eudorella species than the proportions of the articles of extremities. On the basis of this criterion, samples at the Zoological Museum, Hamburg are made up of two species of Eudorella: gracilior and cf. fallax.