Parasitic helminths of Halichoeres bivittatus (Pisces: Labridae) from the southwestern Gulf of Mexico

A total of 326 parasitic helminths were obtained from 94 specimens of Halichoeres bivittatus (Pisces: Labridae) at two sites in the reef zone at the limits of the Veracruz Reef System National Park, Veracruz, Mexico, southwestern Gulf of Mexico: Punta Gorda (n = 51) and Mata de Uva (n = 43). Fish were caught from May to September 2001. Each sample was examined at the levels of the component community and infracommunity. Three parasitic helminth species were found in intestines: Nicolla halichoeri (Digenea: Plagiorchiida: Opecoelidae) is a new geographic record, Procamallanus (Spirocamallanus) garnotus (Nematoda) is a new host record, and larvae of Tetraphyllidea gen. sp. (Cestoda) were the parasites with the highest prevalence and the average intensity at both sites. Species richness (S = 3) and the Shannon-Wiener diversity index (H & PRIME;= 0,42; 0,49) were lower than those previously estimated for the labrid host-parasite community in the study area. No correlations between the total number of species or the total number of helminths and the total length or weight of the host were observed. An analysis of the accumulated curve for the component community suggested that the inventory of helminth species was almost complete for both sites. The abundance of cestode larvae infers H. bivittatus is an intermediate host of the parasite.