Redescription of Parastenocaris brevipes Kessler and description of a new species of Parastenocaris (Copepoda: Harpacticoida: Parastenocarididae) from the U.S.A.

Parastenocaris brevipes Kessler is redescribed and its presence in North America is established through comparison of specimens from the U.S.A., Finland, and Germany. Parastenocaris wilsoni Borutskii, Parastenocaris starretti Pennak, Parastenocaris biwae Miura, and Parastenocaris sp. 2 Strayer (Strayer, D.L. 1988. Stygologia, 4: 279–291.) are assigned to the synonymy of P. brevipes. Biwaecaris Jakobi is a synonym of Parastenocaris Kessler. Some North American records of P. brevipes or P. starretti refer in fact to P. brevipes, other records to a presently undescribed species. Newly verified records of P. brevipes include Massachusetts, Michigan, New Hampshire, New York, Virginia, and Wisconsin in the U.S.A., and Lake Biwa, Japan. Parastenocaris trichelata, new species, is described from Virginia, U.S.A. The taxon is distinguished in both sexes by the combination of the long slender caudal ramus with all setae inserted in the distal half and by the medial spine of the leg 1 basipodite, and in the male by the leg 4 with slender hyaline endopodite and 3 spines on the basipodite medial to the endopodite. The new species little resembles any known North American parastenocaridid, nor is it assignable to any presently defined species-group in the genus.