Alekseev, V.R. (2020). Revision of the genus Mesocyclops Sars 1914 (Copepoda. Cyclopidae) of the world fauna. РЕВИЗИЯ РОДА MESOCYCLOPS SARS 1914 (COPEPODA, CYCLOPIDAE) МИРОВОЙ ФАУНЫ. Zoologicheskii Zhurnal. 99(12):1323-1344. [In Russian; English abstract].
Revision of the genus Mesocyclops Sars 1914 (Copepoda. Cyclopidae) of the world fauna. РЕВИЗИЯ РОДА MESOCYCLOPS SARS 1914 (COPEPODA, CYCLOPIDAE) МИРОВОЙ ФАУНЫ.
The genus Mesocyclops Sars 1914, which has hitherto contained too many nominal species, is divided into four subgenera based on morphological and habitat characteristics. The subgenus Neomesocyclops subgen. n. comprises species almost exclusively living in the New World. The single exception is M. (N.) tenuisaccus (Sars 1927), described from South Africa, which can prove to be a junior synonym of M. (N.) annulatus (Wierzejski 1892), from South America, and could have appeared in Africa as a result of anthropogenic invasion from the New World. The subgenus Tethymesocyclops subgen. n. includes species whose distributions coincide with the borders of the former Gondwana subcontinent, or rather, the coast of the Tethys Sea, during the separation of Gondwana from Laurasia. These two subgenera contain species with a seta on the inner outgrowth of the basal segment of the first swimming leg-pair. This seta is absent from all representatives of the nominative subgenus Mesocyclops s. str. with bare caudal rami and last thoracic somite, as well as from the new subgenus Pilosomesocyclops subgen. n., which shows hairs on these structures. Most species of the latter two subgenera live in water bodies of the Old World. Along with a detailed characterization of the identified subgenera, a new species is described: Mesocyclops (Neomesocyclops) frankfiersi sp, n. As part of the revision, species in the two largest subgenera, Neomesocyclops subgen. n. and Pilosomesocyclops subgen. n., are further divided into three sections by the presence of hair-like structures on the last thoracic somite and/or caudal rami. Sections are named after the first species described that shows these characters. Such a structure of the genus makes it possible to significantly simplify the determination of species in the world fauna and, in the future, to supplement the keys after new taxa are described. Compared to the latest faunal overview by Reid and Ueda, the presented keys are extended to 12 taxa described in the years following the publication of that guide.
