Two new species of free-living marine nematodes, Corononema dhriti sp. nov. (Monhysterida: Xyalidae) and Epacanthion indica sp. nov. (Enoplida: Thoracostomopsidae), from the Tamil Nadu coast, India

Abstract

Two new species of free-living marine nematodes, Corononema dhriti sp. nov. and Epacanthion indica sp. nov. are described from the coastal regions of Tamil Nadu, India. Corononema dhriti sp. nov. differs from the three known species of this genus by a buccal cavity with square anterior portion, spacious and broad, gradually tapering into a conical posterior part; amphideal fovea beneath the buccal cavity and gubernaculum with a distinct knob-like structure.

Epacanthion indica sp. nov. is characterised by the presence of a cervical circle consisting of ten bundles, each composed of approximately ten short setae, located posterior to nerve ring; short spicules (less than 2 cloacal body diameters) and a precloacal supplement. At present, 28 valid species of the genus Epacanthion Wieser, 1953 are classified into four groups based on the male morphology. E. indica sp. nov. is most closely related to the group comprising six species, characterized by a cervical circle of short and dense setae and spicules less than 2 cloacal body diameters.