Potential interactions between the intestinal helminths of the cichlid fish Cichlasoma synspilum from southeastern Mexico

This study presents and analyzes positional data on 18 helminth species for ming the intestinal infracommunities of 59 Cichlasoma synspilum from southe astern Mexico. Interspecific interactions were found between 4 pairs of hos t specialists: Crassicutis cichlasomae (Digenea) with Neoechinorhynchus gol vani (Acanthocephala), Spirocamallanus rebecae (Nematoda) with N. golvani. and Raillietnema kritscheri (Nematoda) with N. golvani. The interactions we re expressed as negative correlations, positional shifts, and reductions in realized distribution. It is suggested that N. golvani produces unsuitable habitats for C. cichlasomae, S. rebecae, and R. kristscheri. All interacti ons were found among phylogenetically unrelated helminth specialists of cic hlids.