Parasite infestation patterns in nine families of coral reef fishes from Saint Martin’s Island, Bay of Bengal

Abstract

The present investigation aimed to observe the parasite infestation patterns in 9 families of coral associated fishes. A total 60 fish individuals were collected from Saint Martin’s Island, preserved and investigated during the study period from June, 2024 to July, 2025. A total of 42 parasites under 8 species were collected from 17 infected fishes. Among them two species of nematode (Camallanus intestinalis and Contracaecum sp.); three species of isopod (Anilocra sp., Cymothoa exigua and Argathona sp.); two species of copepod (Caligus irritans and Lernanthropus sp.); and a single species of pentastomida (Sebekia okavangoensis) were identified. The overall prevalence and intensity of parasites infestation were 28.33% and 2.47 ± 2.4 respectively. The prevalence and intensity of ectoparasites (15%, 2.89 ± 2.8) were slightly higher than the endoparasites (13.33%, 2 ± 1.8). Comparatively higher prevalence and intensity were found in female fish (17.39%, 3 ± 2.4) than in male (10.81%, 1 ± 0) and were found to be statistically significant at p < 0.05 [ectoparasite (χ² = 8.89, p = 0.0117); endoparasite (χ² = 6.84, p = 0.0327)]. Gills and intestines were the most dominant sites where parasites live with the highest prevalence (11.67%) and intensity (3.29 ± 2.8), observed in the gills. On the other hand, the most dominant parasite species were Caligus irritans (21.4%), and Contracaecum sp. (21.4%). Among the length-weight groups of fish, the highest prevalence (100%) was observed in the length between 34.51 cm-37.50 cm, and the 151 gm–200 gm weight groups. However, the prevalence and intensity of parasite infestation in relation to the length and weight of the host fish were not statistically significant.

Dhaka Univ. J. Biol. Sci. 35(2), 73-84, 2026 (July)