Host-parasite interactions between a copepod (Pharodes tortugensis) and small reef-associated gobies (Coryphopterus) in the British Virgin Islands

The effects of parasitic copepods on free-living hosts are infrequently documented, and the copepod Pharodes tortugensis has remained virtually unstudied since described.  For the first time, we document its host range in the British Virgin Islands (BVI), the prevalence and intensity of infections on wild hosts, and its impacts on host morphology and performance.  Infections were observed on four benthic gobies in the BVI (Coryphopterus glaucofraenum, C. venezuelae, C. dicrus and C. eidolon) but not on other host species previously reported from other parts of the western Atlantic.  Infected gobies were widespread in the BVI (detected at 33 of 52 sites, prevalence from 1­–25%) but extremely rare elsewhere in the Caribbean (detected at 2 of 16 sites, prevalence <0.006%).  As is typical of macroparasite infections, P. tortugensis was over-dispersed in BVI host populations (mean intensity = 4.7, range = 1–17).  Infections were most common in juvenile and female hosts, and rarely found i...