Karyology Of Acanthocyclops Kiefer, 1927 (Copepoda, Cyclopoida), Including The First Karyological Reports On Acanthocyclops Trajani Mirabdullayev & Defaye, 2002 And A. Einslei Mirabdullayev & Defaye, 2004

Standard karyotypes of three cyclopoid copepods belonging to the genus Acanthocyclops are reported for freshwater populations from NW Germany and Uzbekistan, namely: A. vernalis (S. Fischer, 1853), A. trajani Mirabdullayev & Defaye, 2002, and Acanthocyclops einslei Mirabdullayev & Defaye, 2004. A comprehensive survey of karyological studies within Acanthocyclops is provided. Species of Acanthocyclops reveal remarkable karyotypic diversity, but also show differences in the mere number of chromosomes, with standard karyotypes ranging from 4 to 12 (2n). Data can provide only limited information on phylogenetic relationships, but are useful diagnostically in clarifying taxonomic boundaries and in separating taxa. Phylogenetic and methodological implications of the karyological findings in Acanthocyclops are discussed.