SURFACE ULTRASTRUCTURE OF NEWLY EXCYSTED METACERCARIAE OF PARAGONIMUS WESTERMANI FROM MALAYSIA AND THE PHILIPPINES

Abstract

We studied the ultrastructure of excysted metacercariae of Paragonimus westermani from Malaysia and the Philippines using scanning electron microscopy. The body surface of the excysted metacercariae was covered with numerous single-pointed and thorn-like tegumentary spines. Dome-shaped papillae were evenly distributed over the whole body and situated circularly around the oral and ventral suckers. Between six to eight and seven to nine small dome-shaped papillae were observed around the ventral sucker in P. westermani from Malaysia and the Philippines, respectively. In general, the morphological features of the worms from Malaysia and the Philippines were identical.