The Taxonomy, Phylogeny and Zoogeography of the Demersal Copepod genus Pseudocyclops (Crustacea: Copepoda: Calanoida) of the world

Abstract

Ten new species of Pseudocyclops (Crustacea: Copepoda: Calanoida) are described from worldwide collections, increasing to 39 the number of species in the genus. A review of the 29 previously known species of Pseudocyclops is included. The origin of the copepods, and evolution within the subclass Copepoda, order Calanoida, and genus Pseudocyclops are discussed. Phenetic and cladistic analyses of the genus are presented. The phylogeny of the genus is compared to its worldwide distribution by using area cladograms constructed upon the phylogenetic tree. These data suggest that Pseudocyclops originated near Australia, with subsequent dispersal eastward across the Pacific Ocean and into the western tropical North Atlantic before the latest Panamanian land bridge was formed. I also hypothesized that Pseudocyclops migrated westward through the former Tethys Sea, progressively colonizing the Indian Ocean, Red Sea, Mediterranean Sea and boreal regions of the North Atlantic.