New Species of the Genus Contracaecum (Railliet and Henry, 1912) from Catfish Wallago attu of Indus River, Sindh, Pakistan

Abstract

A new species Contracaecum malhi collected from catfish Wallago attu Bloch and Schneider, 1801 of Indus river of Sindh, Pakistan. Totally, 41 specimens of host were collected. The host specimens were dissected longitudinally, viscera put into petri dishes for examination of nematodes and were process through standard method of temporary slide. A new species, Contracaecum malhi, were identifed in having differential diagnostic characters such as body shape and size, shape of cephalic end and its structures, ventricular shape, spicule shape and size, numbers and arrangement of caudal papillae, posterior end with 3 rectal gland and large spine at tip, genital structure of female. The name of new species Contracaecum malhi refers to the name of host wallago attu from which the specimens of new species were collected.