title: Detailed surface morphology of the 'lobster louse' copepod, Nicothoë astaci, a haematophagous gill parasite of the European lobster, Homarus gammarus.
abstract: The ectoparasitic copepod, Nicothoë astaci (the 'lobster louse'), infests the gills of the European lobster, Homarus gammarus. There have been limited studies on this haematophagous species; therefore knowledge of this parasite is rudimentary. The current study examines the surface morphology of this parasitic copepod, detached from the host, concentrating on adaptations of the suctorial mouthpart, the oral disc. Cryo-scanning electron microscopy revealed structural adaptations that facilitate attachment of these parasites to the gill filaments of their lobster host. The aperture of the feeding channel, through which host haemolymph is drawn, is only ca. 5μm in diameter. The edge of the oral disc is lined with numerous setae, whilst the surface of the disc is covered with large numbers of small (<1μm in diameter) teeth-like structures, which presumably pierce through, and grip, the cuticle lining of the host's gill. Overall, these structures are thought to provide a 'vacuum seal' to assist in pumping of blood, via peristalsis, into the alimentary canal of the copepod host.
authors.affiliation: Department of Biosciences, College of Science, Swansea University, Swansea SA2 8PP, Wales, UK. Electronic address: cedavies72@gmail.com.
authors.forename: Charlotte E
authors.initials: CE
authors.lastname: Davies
authors.affiliation: Department of Biosciences, College of Science, Swansea University, Swansea SA2 8PP, Wales, UK.
authors.forename: Gethin R
authors.initials: GR
authors.lastname: Thomas
authors.affiliation: College of Engineering, Swansea University, Swansea SA2 8PP, Wales, UK.
authors.forename: Thierry G G
authors.initials: TG
authors.lastname: Maffeis
authors.affiliation: Department of Biosciences, College of Science, Swansea University, Swansea SA2 8PP, Wales, UK.
authors.forename: Emma C
authors.initials: EC
authors.lastname: Wootton
authors.affiliation: College of Engineering, Swansea University, Swansea SA2 8PP, Wales, UK.
authors.forename: Mark W
authors.initials: MW
authors.lastname: Penny
authors.affiliation: Department of Biosciences, College of Science, Swansea University, Swansea SA2 8PP, Wales, UK.
authors.forename: Andrew F
authors.initials: AF
authors.lastname: Rowley
mesh_terms: D000818:Animals; D033342:Copepoda / Q000033:anatomy & histology*; D008855:Microscopy, Electron, Scanning; D008121:Nephropidae / Q000469:parasitology*
keywords: Cryo-scanning electron microscopy; Feeding adaptations; Morphology; Nicothoidae; Parasitic copepod