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Disease. Heterophyiasis

Geographic distribution. Korea and Japan

Infection rate. Unknown in worldwide.

Life cycle. The first intermediate host, snail, is Cerithidea sp. or Tympanotonus sp. The second intermediate hosts are the mullet or goby (Acanthogobius flavimanus). Natural infection of the domestic cats was reported.

Morphology. The adult worm is dorso-ventrally flat, tapering anteriorly, globular and bluntly ending posteriorly, and 0.5-0.8 by 0.3-0.4 mm in size. Neighboring the ventral sucker, genital apparatus present left anterolaterally, 0.06-0.10 by 0.03-0.05 mm in size. Genital apparatus are crescent shape and present two groups of small spine like gonotyls. Intrauterine egg is yellowish brown color, ovoid, operculated, thick shelled, very similar to those of C. sinensis, and 20-23 by 11-13 mm in size.

Pathology and clinical symptoms. Refer to Metagonimus Species.

Diagnosis. Refer to Metagonimus Species.

Prevention. Refer to Metagonimus Species.

Treatment. Refer to Metagonimus Species.

Metacercaria of Pygidiopsis summa from a mullet, Mugil cephalus.

Pygidiopsis summa collected from a cat. Semichon's acetocarmine stained.

P. summa recovered from a dog, which was experimentally infected with metacercariae. Semichon's acetocarmine stained.