Types of cladoceran species described by Sven Ekman in the Swedish Museum of Natural History, with redescription of Daphnia cavicervix Ekman, 1900 (Daphniidae, Anomopoda, Cladocera)

摘要

In the course of our examination of samples of Cladocera from South America and subantarctic islands in the collection of the Swedish Museum of Natural History, Stockholm, we found some type material of Sven Ekman, unrecognized earlier, as well as other samples described in his publications (Ekman 1900, 1905). A single specimen of Pleuroxus scopuliferus Ekman, 1900, apparently seen by its author, is re-deposited as the lectotype, while the neotype of this taxon earlier selected by Frey (1993) must be rejected according to ICZN (2000). Daphnia cavicervix Ekman, 1900 is redescribed based on numerous parthenogenetic, ephippial females and males, and lectotype and paralectotypes are selected. Some recent problems of systematics of Daphnia in South America are discussed.