Insect guide > Bugs > Marsh Treaders

Marsh Treaders


(Family Hydrometridae.)
These are very slender aquatic bugs with a greatly prolonged head. We have only one species, Limnobates lineata Say, which crawls around on soft mud or on water, preferring stagĀ­nant pools.

Life History of a Marsh Treader
(Hydrometra lineata.)
This rather common form is frequently to be found among the aquatic vegetation at the borders of ponds and slow streams. Its life history has been studied and admirably portrayed in the Canadian Entomologist by Mr. J. O. Martin, of Cornell University. The elongated body of the insect is borne on hair-like legs and resembles a bit of twig or grass. There are several generations during the summer, and the insect hibernates as an adult under the rubbish along the banks and lays its eggs early in May. The eggs are laid singly and are glued to the stems of grasses along the stream. They are about two mm. long and are spindle-shaped. The number of eggs must be small, since they are so large that four or five would fill the abdomen of a female. They are covered with a horny coating which has longitudinal ribs, and are marked with a hexagonal pattern.

In seventeen days the young insect emerges from the egg and molts five times before becoming adult. It feeds upon the juices of insects which fall into the water, and, of course, there are many of these along the grassy borders of ponds. Mr. Martin has seen ten of these little water bugs surround a single insect, all of their heads in the direction of common interest, and their bodies radiating outward. The body and legs of the bug are covered with minute hairs which prevents the creature from becoming wet, and it is constantly engaged in lifting its legs into the air and drying them, for if they become wet they sink through the surface film of the water.