Original paper

Notes on morphology and taxonomic status of some North American species of the genus Alona Baird, 1843 (Cladocera: Anomopoda: Chydoridae)

Sinev, Artem Y.

Abstract

Detailed morphology of three North American species of the genus Alona Baird, 1843: A. bicolor Frey, 1965, A. circumfimbriata Megard, 1967 and A. setulosa Megard, 1967 was studied for the first time. The taxonomic status of these species is now clarified. A. bicolor belongs to the costata-group. Unlike to other species of the group, it demonstrates strong adaptation to benthic habitats - incl. thick carapace, a elongated rostrum and reduced eye. A. circumfimbriata is a member of rectangula-group, and its closest relative is the tropical A. monacantha Sars, 1901, differing in morphology of postero-ventral angle of valves and exopodite of limb III. A. setulosa has numerous characters in common with the species of the pulchella-group, but the relationship is more distant than in two other discussed species.

Keywords

cladocerachydoridaealona bicoloralona circumfimbriataalona setulosamorphologynorth america