A Redescription of the Bulla, Antennae, and Mouth Parts of Female Clavella sp. (Copepoda: Siphonostomatoida: Lernaeopodidae) Infesting Wild Gadus morhua Using Scanning Electron Microscopy (SEM).

Harry M Murray,Corey Morris,Jacqueline M Hanlon,Kimberly Marshall,Bernard Marchand

doi:10.1155/2020/8891448

Abstract

Many members of the Copepod family Lernaeopodidae are well-known parasites of gadids. This study reports on the occurrence of a lernaeopodid infestation of wild-sourced Gadus morhua sampled from separate inshore (Gilbert Bay, NL) and offshore (Virgin Rocks, NL) populations from Newfoundland, Canada. The majority of the parasites were observed to be associated with the buccal cavity, gill filaments, gill arch, and occasionally near the outer edge of the operculum. Anatomical analysis and detailed redescriptions of the parasite's functional anatomy (mouth parts, antennae, and bulla complex) using high-resolution SEM indicated that the parasite was most likely of the genus Clavella. New morphological details of the second antennae ornamentation, first maxillae, bulla complex, and the oral cone are provided and discussed with regard to their potential in taxonomic applications.

Highlights

Copepods are small, abundant, inconspicuous aquatic crustaceans
The female generally utilizes a characteristic chitinous attachment organ called the bulla to attach to the host permanently [2, 4]
In December 2019 during routine measurements, a number of fish independent of origin were noted to present with a presumptive parasitic copepod infestation

Summary

Introduction

11 500 species are known, half of which are symbiotic with most of those being parasitic and exhibiting a broad host specificity [1]. Members of the copepod family Lernaeopodidae are parasitic mainly on marine fish, including both Selachii and Teleostei [2]. Boxshall [3] reported up to 45 different genera from this family parasitic on teleosts and some elasmobranch fishes. As is common in parasitic copepods, the Lernaeopodidae display an unusual sexual differentiation. The female is attached as a parasite on the host. The small male lives in temporary association, often on the body of its partner. The female generally utilizes a characteristic chitinous attachment organ called the bulla to attach to the host permanently [2, 4]

Methods

Results

Conclusion