Introduction to the first symposium on the biology of the parasitic Crustacea.

The parasitic Crustacea represent a diverse group with members in several classes and orders, including the Cirripedia, Isopoda, Amphipoda, Branchiura, Copepoda, Tantulocarida, and Pentastomida. Their biology is as diverse as their morphological and phylogenetic disparity would indicate, and includes egg mimicry, parasitic castration, host feminization, epigametic sex determination, venomous secretions, and bizarre adaptations of the life cycle. However, convergent adaptations to the parasitic lifestyle are common and must be considered when studying the evolution of the organisms, their behaviors, and morphological modifications. Recently, there have been several important papers on the evolution of parasitic crustaceans, but most of these have covered narrow groups, such as the Rhizocephala (e.g. Hoeg 1995, Schram & Hoeg 1995, Hoeg and Lutzen 1996) and the parasitic copepods (e.g. Huys and Boxshall 1991, Ho 2001, Boxshall 2004). Additional papers have highlighted interesting biological attributes of specific parasitic groups, such as polyandry in sea lice (Todd et al. 2005), host preferences, and ecological effects in nicothoid copepods (e.g. Shields et al. 2006 for a review of those on lobsters), and even the effects of climatic warming on species of Argulus (Hakalahti et al. 2006). Such papers have provided new data and new ways of looking at these organisms that give insights into questions about their broader biology. Given the continued interest in the adaptations of parasitic crustaceans, as well as in the effect of these organisms on important aquaculture and fishery species, we organized a symposium at the Society for Comparative and Integrative Biology (SICB) meeting in Boston for 2009, to provide a reference point for broader discussions on the topic. The symposium was structured with topics in evolution, life history, molecular biology, and pathology. As far as we know, there have been no other symposia devoted entirely to the parasitic Crustacea; thus, the First Symposium on the Biology of the Parasitic Crustacea was held at the SICB Annual Meeting, in Boston, January 4–5, 2009. However, it is important to note that there have been several specialized symposia on diseases of Crustacea (Symposium on Diseases of Commercially Significant Crustaceans, International Crustacean Conference VI, Glasgow, 2005; The Biology of the Rhizocephala, The Crustacean Society Annual Meeting, Williamsburg, 2003; Diseases of Crustacea, National Shellfisheries Association Annual Meeting, Mystic, 2002; as well as several on viral infections in shrimp) and a few symposia on specific taxonomic groups such as the parasitic copepods of fishes (e.g. Symposium on the Parasites of Fishes and Other Aquatic Organisms, IX European Multi-colloquium of Parasitology, Valencia, 2004; V International Symposium on Fish Parasites, Ceske Budějovice, 1999; Sea lice and Other Parasitic Copepoda, 1st European Crustacean Conference, Paris, 1992). Hence, our attempt to encompass a broader view of parasitism across the Crustacea was timely and provided an opportunity for experts in diverse taxa to compare and contrast questions broadly between systems. The program for the symposium was organized around different taxonomic groups. There were 11 primary papers in the symposium and five in a complementary session. Several of the papers were reviews of the existing literature. The papers given were: