Thelohanellus habibpuri sp n. (Myxozoa : Bivalvulida) from the tropical freshwater fish rohu, Labeo rohita (Hamilton-Buchanan, 1882) in West Bengal, India: Light and electron microscope observations

摘要

A new species of myxozoan (Myxozoa: Bivalvulida) Thelohanellus habibpuri sp. n. parasitic in tropical freshwater fish collected from the Habibpur, West Bengal, India is described in this paper. T habibpuri was found in the Pectoral fin of Labeo rohita (Hamilton-Buchanan, 1882). The diagnostic characters of T habibpuri are: generally oval milky-whitish plasmodia attached in the pectoral fin of host fishes; spore egg-shaped to ovoid with slightly tapering anterior and rounded posterior end, averaging 13.9 x 8.5 mu m in size; a single oval-round polar capsule 6.0 x 4.9 mu m in diameter, with polar filament wound in 3-4 coils. Finely granular sporoplasm containing two slightly oval nuclei (1.4 mu m in diameter) and a small iodinophilous vacuole (3.0 mu m in diameter) present in the spore. SEM study of this myxozoan reveals the anterior extremity of spore is truncated. The Cnidocyst discharge channel appear as a dark area. The longitudinal wavy surface are visible on the spore.