Scanning Electron Microscopy and First Molecular Data of Two Species of (Copepoda: Lernaeidae) from (Cyprinidae) and (Clariidae) in Kenya.

A parasitological study carried out in May 2022 and March 2023 in the Nyando River of Lake Victoria Basin, Kenya, disclosed two parasitic lernaeid copepods: Humes, 1957, from the gills of a cyprinid, the Ningu Boulenger, 1901, endemic to the Lake Victoria drainage system, and Fryer, 1957, from a clariid, the North African catfish (Burchell, 1822). The copepods were studied and supplementary taxonomic information was presented using scanning electron micrographs and genetic data. Scanning electron microscopy (SEM) provided information on the morphology of 's antennae, oral region, thoracic legs (2-5), and furcal rami not previously reported. Analyses of the partial fragments of 18S and 28S rDNA and cytochrome oxidase subunit 1 (1) of the two parasites showed them to be distinct from all other taxa retrieved from GenBank. This study presents new taxonomic information on morphology using SEM and provides the first ribosomal (18S and 28S rDNA) and mitochondrial (mtDNA) data for these two parasite species. The 1 data provided are the first for all 38 nominal species of . Notably, the study also provides a new host record for and extends the geographical information of this species to Kenya.