LAUSR

Coastal lagoons are an important component of the Gulf of California as they are considered natural ecosystems with high productivity and home to species of regional economic interest such as the striped mullet ( Mugil cephalus ), which, for its eating habits tends to present parasitism. The objective of the present work was to identify and determine the number of nematode parasites in the striped mullet in three lagoon systems (Navachiste, La Reforma, and Ceuta) in coastal areas of the southern Gulf of California. Thirty Mugil cephalus were randomly obtained from each of the lagoon systems. From each fish was obtained the total length, weight and condition factor (FC), next was dissected to be analyzed hepatosomatic index (HSI) and determine by direct count the prevalence, average intensity and average abundance of nematode; nematodes are identified taxonomically and molecularly. The nematode parasites found to belong to the genus Contracaecum of the family Anisakidae in all the fish sampled the parasitic prevalence was 67%. The nematode parasites found by sex indicated that 77% of the striped mullet females analyzed were parasitized, while the males presented 59%. The CF obtained was 1.17- 4.07, and the HSI ranged between 0.85 and 1.45; the average intensity for nematodes was 7.45, and the average abundance was 4.97, demonstrating that Contracaecum multipapillatum is the main nematode parasite present in all lagoon systems the southern Gulf of California.