SEM studies on acanthocephalan parasite, Echinorhynchus veli infecting the fish Synaptura orientalis (Bl & Sch, 1801).

Echinorhynchus veli (George and Nadakal, 1978), an acanthocephalid worm infesting the estuarine flat fish, Synaptura orientalis, was collected from the Veli lake, Kerala. The parasite was recovered from the intestine of the host fish. The detailed surface morphology was studied with the help of scanning electron microscope. The study revealed a cylindrical, medially swollen proboscis with a flat apex, backward directed hooks, each with smooth surface, broad base, pointed tip and an epidermal elevation at the point of insertion. A pair of sensory pits was seen at the base of the proboscis. The neck was well developed with densely packed epidermal micropores. Paired sensory pits were seen at the base of the neck and a collar between it and the trunk. The epidermis of the trunk has microtriches and micropores. The female genital pore was circular, and terminal in an elevated orifice. In male, the copulatory bursa was directed ventrally, with well-defined rim and several sensory papillae.