Abstract
Benedenia (Capsalidae) is a genus of important oral and cutaneous fluke parasite of aquarium, cultured and marine fish. In the present study, the morphological and morphometric characterization of Benedenia sciaenae, a monogenean parasite infecting the gills of the brown-spotted grouper fish Epinephelus chlorostigma were described by means of light microscopy as a first description from Epinephelus chlorostigma. 215 out of 290 (74.1%) fish samples were found to be infected with this ectoparasitic capsalid causing pathogenic and epizootic events. The adult worm is flattened, elongated with an anterior adhesive organ enclosing two anterolateral adhesive structures, each one possesses three lobes which aids for adhesive secretions while the enlarged posterior end enclosing haptor. The adult worm measured about 0.52 -0.67 (mean 0.59 +/- 0.03) mm in total length and 0.33 - 0.49 (mean 0.38 +/- 0.02) mm in width. Haptor width measured 0.25-0.29 (mean 0.26 +/- 0.02) mm; its hard parts consist of two pairs of hamuli and the accessory sclerites. The anterior hamulus measured 0.027-0.034 (mean 0.31 +/- 0.002) mm long while the posterior one measured 0.030-0.040 (mean 0.036 +/- 0.002) mm and each of the accessory pieces measured 0.032-0.044 (mean 0.040 +/- 0.002) mm long. Results showed that the general morphology of the present Benedenia sp. resembles that of B. sciaenae described previously in Turkeys from Argyrosomus regius fish host with the dimensions of body more or less similar. Also, there were significant correlations (P <= 0.05) between fish length, weight and parasite abundance per fish. Number of monogeneans was increased with host size and age to fish of intermediate length and weight, and then it decreased probably because changes in size of gill filaments affect their attachment capability, enhancing the possibility of being detached by respiratory currents. [Kareem Morsy; Sayed Abdel-Monem; FathyAbdel-Ghaffar; Abdel-Rahman Bashtar; Ali Al-Ghamdi and Rania Abdel-Gaber First record of Benedenia sciaenae (Monogenea: Capsalidae) infecting the brown-spotted grouper fish Epinephelus chlorostigma (Family: Serranidae) from the Red Sea in Egypt] Life Science Journal,. 2011; 8(4):245-252] (ISSN: 1097-8135).