Identification of some monogenetic treamatodes from some Arabian Gulf fish in Saudi Arabia.

Examination of 90 Epinephelus chlorostigma and 50 Lethrinus nebulosus reaveled that 99% of the former harboured monogenea belonging to two species. (1) Megalocotyloides epinepheli Bychowsky and Nagibina, 1976 (Encolyllabe), 1-6 worm per fish, from buccal cavity, attached to lower pharyngeal plate between teeth. (2) Pseudorhabdosynochus epinepheli Yamaguti, 1938 (Diplectanum), over 100 worms per fish from the gills. On the other hand 4% of L. nebulosus harboured another two species of monogenea (1). Polylabris angifer Hussey, 1986, 1-2 worms per fish from the gills. (2). Polylabris sp. only one worm from the gills. As far as it can be concluded. this is a new locality and new hosts of the four species of worms.