Abstract
Paragonimus eggs, metacercariae, and adult worms from Guatemala were morphologically examined using a light and scanning electron microscope. On average, the eggs measured 71 micron m x 42 micron m. The brown egg shell was thin and shallow pits covered the surface. The mean measurements of the fixed metacercariae were 1,156 micron m in length. The ventral sucker was larger than the oral one. On average, 25 outer-papillae were counted. The flame cell formula showed 2[(3+3+3+3+3)+(3+3+3+3+3)}=60. The adult worms fixed in 10 % formalin under the pressure of a slide glass measured 8.9 mm in length x 4.2 mm in width, and the oral and ventral suckers measured 512 micron m x 640 micron m, respectively. The ovary was delicately branched. These results showed the features of Paragonimus mexicanus.
Key words: Paragonimus mexicanus; adult worm; metacercaria; egg; morphology; Guatemala.