The Occurrence of the Asellote Isopod Genera Haplomesus (Ischnomesidae) and Haploniscus (Haploniscidae) in Antarctica, with Two Redescriptions and Description of Ischnomesus curtispinis n. sp

Two species of the Ischnomesidae, Haplomesus quadrispinosus (SARS, 1879) and Ischnomesus curtispinis n. sp., and one species of the Haploniscidae, Haploniscus antarcticus VANHÖFFEN, 1914, have been sampled with the RV “Polarstern” in Antarctica. As the hitherto published descriptions are incomplete, a complete redescription of these species is presented in order to allow phylogenetic analyses. In a final discussion the probable biogeographic origin of these species is presented.