Complementary description of Ergasilus arthrosis Roberts, 1969 (Copepoda: Poecilostomatoida: Ergasilidae), a new parasite of cichlid teleosts in southeast Mexico

Abstract

During a parasitological survey of the ichthyofauna of Lake Catemaco, a freshwater system in the Mexican State of Veracruz, the widespread copepod Ergasilus arthrosis Roberts, 1969 was recovered from two cichlid teleosts, Mayaheros urophthalmus (Günther) and Oreochromis sp. This is the first confirmed record of this copepod species outside of the United States and from Mexico; its finding as a parasite of cichlids represents an expansion of the known host range for this copepod. The local prevalence and intensity of infection of E. arthrosis was highest in M. urophthalmus. The infection prevalence of E. arthrosis on M. urophthalmus (60%) was higher than that known for other ergasilids on cichlids. Ergasilus arthrosis can be distinguished from its closest congener E. lizae Krøyer, 1863 by the morphometry of the antennary segments, the ventral ornamentation of the thoracic sclerites and by details of the antennulary setation, but also by its habitat and host preferences. Taxonomic illustrations and morphological details of the specimens examined are also provided together with comments on the variability of this species.

Integrative Morphological and Genetic Characterisation of the Fish Parasitic Copepod Ergasilus mirabilis Oldewage & van As, 1987: Insights into Host Specificity and Distribution in Southern Africa

“…The attachment of ergasilids may result in the compression of gill tissue [9], host immune responses such as increased production of mucous and rodlet cells [10,11] and necrosis of the gill filament, ultimately making hosts susceptible to secondary infections (see [10,12] and the references therein). Due to their importance in biodiversity studies and the economic importance of some species (such as Ergasilus sieboldi von Nordmann, 1832 and E. lizae Krøyer, 1863) in the aquaculture and fisheries industry, there have been numerous publications focusing on the taxonomy, feeding, pathology, and lifecycle of ergasilids [13][14][15][16][17][18][19][20][21][22][23]. The general body morphology of a typical ergasilid, whether male or female, is cyclopiform with a swelling in the prosome somites of females, and members of the Ergasilidae are characterised by the loss of the maxillipeds in females [1].…”