Abstract
Fairfaxia lethrini, gen. et sp. nov., is described from the intestine of Lethrinus chrysostomus from the southern Great Barrier Reef. The new genus is characterised by its large ventral sucker which interrupts the vitelline fields, small cirrus pouch and median genital pore, short excretory bladder and small post-testicular field into which neither the vitelline follicles nor the caeca extend.