Pseudopycnadena tendu sp. nov. is described from the balistid Pseudobalistes fuscus from the waters off New Caledonia. It differs from the only other member of the genus P. fischthali Saad-Fares et Maillard, 1986, in its broad cirrus-sac, with the wide field of large gland-cells, its less nearly circular body shape, its dorsal excretory pore, its shorter post-testicular region, its relatively larger ventral sucker and its smaller eggs. The genus is re-defined to take these distinctions into account. Other opecoelid species reported from New Caledonia are Allopodocotyle epinepheli (Yamaguti, 1942)