Meeting Abstract

S2.3  Sunday, Jan. 4  The comparative biology of Copepoda parasitic on three host taxa: fishes, polychaetes and crustaceans. BOXSHALL, G.A.; The Natural History Museum, London g.boxshall@nhm.ac.uk

The Copepoda is one of the mega-abundant arthropod taxa on Earth and, although most copepods are free-living, about one third of known species live in symbiotic associations. They have moved into symbiotic life-styles independently on numerous occasions, in distinct lineages, and have come to exploit an enormous range of phyla as hosts, from sponges to chordates (including mammals). In this account I focus initially on aspects of the biology of copepods that utilise fishes as hosts. Over 2000 copepod species are parasitic on fishes and these are currently classified within 27 families. The largest of these families is the Caligidae, the sea lice, which includes some of the most serious pests in commercial finfish aquaculture, and causes economic losses in excess of $100 million per year. At the other end of the host spectrum are the crustaceans which, if we exclude the various taxa that live in loose symbiotic relationships with their crustacean hosts, serve as hosts to only a single family of parasitic copepods, the Nicothoidae. Between these host spectrum extremes lie the polychaetes which serve as hosts to 16 families of copepods, but most of these are rarely encountered. This paper compares aspects of the biology of the copepods found on fishes, polychaetes and crustaceans as hosts, including life cycles, extreme morphologies, feeding mechanisms and patterns of species richness.