Lamproglena monodi Capart, 1944 infecting Oreochromis niloticus (Linnaeus, 1758): additional information on infection, morphology and genetic data

Abstract

Lamproglena monodi Capart, 1944 adult females were first described from the Democratic Republic of the Congo and have been redescribed seven times from different cichlid species in Egypt, Burkina Faso and Brazil, all showing morphological variation. The adult male was first described from Lake Victoria and the Victoria Nile in Uganda. Copepods from the present study were collected from the gills of Oreochromis niloticus (Linnaeus, 1758) from Kibos Fish Farm, Kenya (between December 2017 and April 2018) and Sharqia Governorate (June 2019) and El-Minia (between July and December 2018) in Egypt. They were identified as L. monodi based on morphology and genetic data. Parasites were studied morphologically with the aid of light microscopy and scanning electron microscopy (SEM), and female infection levels calculated. Genetically, the specimens were studied using fragments of 18S and 28S rDNA. SEM analyses revealed additional diagnostic morphological features for the three adult males (elusive) and 249 females. These data were used to update the identification key for male Lamproglena species. Prevalence, mean intensity and mean abundance of the females were calculated as 13.5%, 8.6 and 1.2 respectively. Both 18S and 28S rDNA fragments confirmed the distinctness of L. monodi from previously characterised Lamproglena species, with distances of 1.22–1.94% (17–27 bp) for 18S rDNA and 15.66–18.1% (111–128 bp) for 28S rDNA. Haplotypes obtained from male and female specimens were identical, confirming the identity of the male specimens. This is the first genetic study of Lamproglena from Africa, the first SEM and genetic study of male L. monodi, and the first geographical report of this parasite from Kenya. The male and molecular data reported herein provide a useful point of reference for future Lamproglena studies.