Amenbo: Gerridae

Gerridae Aquarius paludum paludum, which have long legs for living a life on the water, includes Hemiotera Gerridae. In Japanese, the name is Amenbo but there are many kinds elsewhere, and it is classified in different ways. The appearance is different by a course, but the basic structure of the body such as a feather or a way of speaking is the same as Hemiotera. Gerridae has stink gland in a body that smell like candy, from which the Japanese name is derived (ame is candy).

The larva and imago are flesh-eating. They eat insects which fell into surface of the water by injecting digestive juice and body sucking the fluid. When Gerridae looks for game, it senses a small ripple occurs on the surface of the water and catches a position of the game.

Gerridae supports itself on its fore legs and hind legs and uses its middle leg to kick the surface of the water and move. The quick jump is possible by how to kick surface of the water. However, it uses all six legs to moves on foot like a land model.

There are many kinds of Gerridae inhabiting Japan. I took up three kinds in Gerridae. Aquarius elongates is biggest Gerridae in Japan and the length is 19-27mm. Not only the body but also a leg and the antennae are long. The length is markedly big in comparison with other markedly, and Gerridae. Aquarius elongates inhabit the gentle ponds and rivers of the flow and seen in Honshu, Shikoku and Kyushu for from May to October.

Aquarius paludum paludum are called Amenbo or Namiamenbo in Japanese. The length is 11-16mm and it seen commonly in Japan. Aquarius paludum paludum inhabit the gentle pond and marsh without the flow and it is seen from April to October. Geris lacustris length is 8-11mm small, Gerridae resembles Aquarius paludum paludum closely. The slight hair of the silver gray grows to both sides and the forewing of the prothoraces rear one. Geris lacustris inhabits gentle ponds and marsh, the puddle of the flow and it seen in Japan from May to October.

Gerridae is distributed widely from the tropical zone to the subarctic zone and it is an aquatic insect distributed over the various surfaces of the water the small puddle, pond, lake, river and sea. It the day of the early fall, it is seen making a big crowd. In winter, it enters the land and winter in the bottoms of fallen leaves. They mate from April to July.

The female diving underwater and carried a male on board and lays an egg to the stem of the waterweed. The egg hatches in about 10 days and larva molt five time to became imago.

Gerridae float on surface by surface tension. Water pollution by life drainage and seawall main tance, then surface tension weaken. Gerridae drown. So Gerridae is environmental work.

Because Gerridae habitation over a wide area, can be seen many watersides.