Insect guide > Bugs > Chinch Bugs

Chinch Bugs


(Family Lygaeidae.)
This is one of the large families of plant bugs, comprising rather more than 1300 species, distributed in thirteen subfamilies and 208 genera. Of these about 175 species are known in the United States. No good popular name has been proposed for this group. Comstock calls it the "chinch-bug family " from its most famous representative, but of course this is not a distinctive name.

The Lygaeids are distinguished from other bugs chiefly by the membrane of the front wing, which has four or five simple veins, and by the antennae, which are inserted low down on the side of the head. Many of these bugs, when full grown, have the wings either long or aborted, so that in the same species there are both long­winged and short-winged forms. All live on the juices of plants, and the family contains many injurious forms. The most prominent of these is the chinch-bug (Blissus leucopterus), a little bug which occurs in Central America and the West Indies and all over the United States and north into Canada. It feeds on Indian corn and on wheat and other small grains and grasses, puncturing the stalks, and
causing them to wilt.

Its great notoriety as a crop destroyer arises from the incalculable numbers in which it appears in dry seasons. The average annual loss which this insect causes to the United States is in the millions of dollars.

Another very common and destructive insect belonging to this family is the so-called "false chinch-bug" (Nyzius angustatus Uhl.) which although it belongs to a different subfamily is frequently mistaken by farmers for the true chinch-bug. It damages grapevines, strawberry plants and many garden vegetables, puncturing the leaves with its beak and causing them to wilt. The life history of this bug should be worked up. We do not know its eggs, the number of molts or the number of generations. One of these bugs, known as Belonochilus numideus Say, according to Heidemann, feeds on sycamore leaves and passes the winter, in the half-grown condition thrust down in the crevices of the "button balls".

Life History of the Chinch-Bug
(Blissus leucopterus Say.)
The chinch-bug is a small, dark colored insect with white wings. It is only 3 mm. long and is rather slender. It passes the winter as a full-grown bug, hidden away in clumps of old grasses or in other protected spots. The egg is nearly 1 mm. long, elongate-oval, and of an amber color. About five hundred are laid by each female and are thrust into grass sheaths near the ground, or upon the stem at or under the surface of the ground. They are laid in the spring and the young hatch soon afterwards. The newly hatched bugs are pale yellow at first but grow red. They molt four times before becoming adult and grow darker in color and the adult is dark gray or nearly black.

Over most of the United States there are two generations, the eggs for the second generation being laid in late July or early August. In all stages the chinch-bug is gregarious and clusters upon grains and grasses in such numbers as to quickly destroy them. They migrate in search of food and after wheat harvest they usually travel to the nearest cornfield and the second generation is developed on this crop. Many of the adults have only half developed wings and this form, which is called "micropterous" is apparently more abundant near the sea-coast than elsewhere. A fungus disease is very prevalent in wet weather and efforts have been made to propagate this disease and artificially introduce it into infested fields.