Indocapillaria gibsoni n. g., n. sp. (Nematoda: Trichuroidea) from the estuarine fish Sillaginopsis panijus (Hamilton) of West Bengal,India

A new nematode from the stomach of the estuarine fish Sillaginopsis panijus of West Bengal, India is described. The nematodes are characterised by small body size, the structure of the male tail (the presence of two large dorso-lateral caudal lobes bearing a distinct papilla on each and a pair of large subventral adanal papillae), the structure of the spicule (wider in proximal and distal regions and with smooth surface), the non-spinous spicular sheath, the structure of the stichosome (stichocytes number 25–32 and regularly aligned throughout the length of the oesophagus), the large bell-shaped vulvar appendage, and elongate-oval eggs with a thin wall and protruding polar plugs. A diagnosis of the new genus and a key to the genera of fish capillariids are provided.