Abstract
<jats:title>Abstract</jats:title> <jats:p>In this chapter the authors describe patterns of trophically transmitted helminths parasitizing marine fishes from the southeastern Pacific Ocean. They include both presence–absence data of a published host–parasite checklist for 101 marine fish species off the coast of Chile and a separate study with previously unpublished data from the rocky intertidal fish assemblage (N = 17 fish species) inhabiting tidepools in the Biobio region, Chile. The general aim is to show patterns that emerge when the data is analyzed on a host/parasite community assemblage basis, rather than on a host species-by-species basis. The novelty of their approach lies in its integration of dietary and spatial variability in the analysis of parasite–host interactions as well as the use of parasite biovolume (≈ biomass) to describe the distribution of parasites in host assemblages. Results show that (1) generalist parasites are informative indicators of host habitat; (2) assemblages of trophically transmitted helminth parasites in the fish assemblage of rocky intertidals are numerically dominated by generalist species, and dietary overlap among hosts is not correlated with similarity among parasite communities; (3) density of parasites (by numbers and biovolume) decreases with host body mass due to a faster rate of increase of host body mass than the rate of increase of parasite numbers or biovolume.</jats:p>