Redescription and Molecular Identification of Proctotrema prominens (Monorchiidae: Odhner, 1911) from Parupeneus forsskali, a Red Sea Goatfish in Egypt

Proctotrema prominens, a trematode parasite originally identified by Wee, Cribb, and Cutmore in 2022 and belonging to the Monorchiidae family described by Odhner in 1911, was recovered from the intestinal tract of the Red Sea goatfish, Parupeneus forsskali, in the Red Sea region of Egypt. The prevalence rate of the parasite was found to be 42.6%, with a distribution of 51.5% in males and 34% in females. Morphologically, the parasite displayed a slightly fusiform body with a funnel-shaped oral sucker larger than the ventral sucker, a single testis, a cylindrical cirrus sac, a smooth ovary, an unspined genital atrium, caeca extending posteriorly into the post-testicular zone, and terminating near the posterior extremity. Molecular techniques utilizing IST2 rDNA facilitated the accurate identification of the parasite. Comparative analysis of the IST2 sequence against available monorchiids on GenBank confirmed the parasite's classification within the P. prominens clade. This study represents the first redescribed instance of P. prominens from a novel fish host, Pa. forsskali, of the Mullidae family described by Rafinesque in 1815, discovered in the Red Sea near Safaga, Egypt, marking a new geographical locality for this species.