Predation of frog eggs by the water strider Gerris latiabdominis Miyamoto (Hemiptera: Gerridae)

Water striders (Hemiptera: Gerridae) are predators found on the water surface that prey mainly on arthropods. The feeding on other organisms (dead vertebrates, fishes and tadpoles) is a rare event. To our knowledge, predation of frog eggs by water striders has not yet been reported. We observed that adult water striders, Gerris latiabdominis Miyamoto, 1958 (Hemiptera: Gerridae), preyed on the eggs of three frog species, Pelophylax nigromaculata Hallowell, 1861 (Anura: Ranidae), Rana japonica Boulenger, 1879 (Anura: Ranidae), and Rhacophorus schlegelii Günther, 1858 (Anura: Rhacophoridae). We found predation by the water striders affects the survival rate of frog eggs floating on the water surface. We suggest that this hunting event would occur in water bodies in which water striders and frogs coexist, especially the region where their phenology overlaps. Water striders prey mainly on terrestrial insects, dead vertebrates, fishes and tadpoles. However, to our knowledge, predation of frog eggs by water striders has not yet been reported. We observed that adult water striders, Gerris latiabdominis, preyed on the eggs of three frog species.