Studies on metacercariae from naiads in northeast Thailand
Adam, R.; Sithithaworn, P.; Pipitgool, V.; Hinz, E.; Storch, V.
Southeast Asian Journal of Tropical Medicine and Public Health 24(4): 701-705
1993
ISSN/ISBN: 0125-1562 PMID: 7939944 Document Number: 407401
In an investigation of the life cycles of Phaneropsolus bonnei and Prosthodendrium molenkampi, 111 naiads of 6 dragonfly species (Ictinus angulosus, Crocothemis servilia (the most abundant species: 43 of 72 were infected), Hydrobasileus croceus, Brachythemis contaminata, Orthetrum sabina, Trithemis pallidinervis) from Khon Kaen Province, Thailand, were investigated for the presence of metacercariae. Sixty-nine (62.2%) were infected with intensities up to more than 150 cysts/individual (I. angulosus were infected with a mean of 135 metacercariae/individual, C. servilia with a mean of 26/individual, and the rest with from 1 to 7 cysts/individual). The metacercarial cysts were characterized by light and scanning electron microscopy. Two types of metacercariae were differentiated by morphological features of the cyst surface, cyst wall and size. Both types of metacercariae were fed to mice and gerbils, but no infections developed.