Network metrics and community structure
We identified 42 meta-communities in the cichlid-Cichlidogyrusnetwork through the Louvain algorithm. Several detected meta-communities that included only few species and were completely unconnected to the other communities formed part of LT (Fig. 2a). Four meta-communities other than LT and LV (Fig. 2b) included 10 or more species (Fig. 2c; Appendix S4): the ‘Coptodon zillii ’ (CZ ), ‘Oreochromis niloticus ’ (ON ), ‘Hemichromis ’ (He ), and ‘Tilapia sparrmanii ’ (TS ) clusters. These names reflect the host taxa accounting for a majority of reported infections (Appendix S1.2). Network structure differed between meta-communities but anthropogenic introductions had only a limited effect (Fig. 3; Appendix S1.2).