Molecular phylogenetics and biogeography of Bunodera spp. (Trematoda: Allocreadiidae), parasites of percid and gasterosteid fishes

Abstract

The genus Bunodera Railliet, 1896 is represented by five freshwater species: the holarctic B. luciopercae (Müller, 1776) in percids; the endemic North American B. sacculata VanCleave and Mueller, 1932 in percids; B. eucaliae (Miller, 1936) and B. inconstans (Lasee, Font and Sutherland, 1988) in freshwater sticklebacks; and the trans-Pacific B. mediovitellata Tsimbaliuk and Roytman, 1966 in the threespine stickleback (Gasterosteus aculeatus L., 1758). Partial sequences of the 28S ribosomal RNA gene were combined with morphological data for a phylogenetic analysis of Bunodera spp. Parsimony analysis of the combined data yielded a tree (consistency index = 0.84) that supports the following resolution: ((((B. luciopercae(((B. sacculata((B. mediovitellata(B. eucaliae + B. inconstans)))). The basal position of B. luciopercae is consistent with its holarctic distribution and a basal percid as its main host. The relatively basal positions of two typical perch parasites and the association of a more derived clade (B. mediovitellata + B. eucaliae + B. inconstans) with sticklebacks indicate host shifting from percids to sticklebacks. The sister relationships and North American endemicity of the two most derived species, B. eucaliae and B. inconstans, are also consistent with the more derived position of their typical host, the freshwater brook stickleback (Culaea inconstans (Kirtland, 1841)).