Two new gonad-infecting species of Philometra (Nematoda: Philometridae) parasitic in Lutjanus spp. (Osteichthyes: Lutjanidae) in the Bay of Bengal, India.

Abstract

Based on light and scanning electron microscopical studies, two new gonad-infecting species of Philometra Costa, 1845 (Nematoda: Philometridae) are described from marine fishes of the genus Lutjanus Bloch (Lutjanidae, Perciformes) in the Bay of Bengal, off the eastern coast of India: Philometra argentimaculati sp. n. and Philometra fulvi sp. n. from the mangrove red snapper Lutjanus argentimaculatus (Forsskål) and blacktail snapper Lutjanus fulvus (Foerster), respectively. P. argentimaculati is mainly characterised by the body length of male 2.56-3.07 mm, needle-like spicules 183-228 μm long, length of the gubernaculum at 90-120 μm, distal end of the gubernaculum with lamellar structures without a dorsal protuberance and by the dorsally non-interrupted male caudal mound. P. fulvi differs from all Philometra spp. with described males in the rectangular shape of the distal tip of the gubernaculum and is noted for the length of needle-like spicules 123-138 μm, that of the gubernaculum 69-93 μm and for the presence of a dorsal protuberance and lamella-like structures on the gubernaculum distal end. These are the first nominal species of philometrids reported from fishes of the family Lutjanidae in the region of the Indian Ocean. A necessity of further detailed studies on philometrids parasitising marine fishes worlwide is stressed.