The Water Penny Beetle
The insect I'm doing for my project is the Water Penny Beetle. The phylum of this insect is Arthropeda. The class is Insecta, the order is Coleoptera, and the family is Psephenidae. The Water Penny Beetle has extended flanges which resemble suction cu[s and have five pairs of finger-like gills on the front. Adults are brown or black oval with soft bodies measuring from 4.5 to 6 millimeters in length.
The life cycle of the water penny beetle lasts from 21 to 24 months. They deposit between 400 to 600 eggs in a 5 centimeter square patch. The bright yellow eggs are from 0.5 to 2 millimeters in diameter. Egg laying usually occurs from June to late August, and hatching occurs in 12 to 15 days.
After hatching, larvae grow rapidly, feeding on small crustaceans and free-floating algae. The larvae don't feed or molt during the following winter but pupate during the next spring or summer.
When maturation is delayed until fall, the larvae overwinter again and pupate the following spring. Larvae pupate above water and may be damaged by high water levels or by wasps. Both male and female adult beetles emerge from June to September, mate, and lay eggs immediately. Adults live from 2 days to 1 week and eat little or nothing.
Water penny beetles larvae live wherever eggs are deposited and distributed by water flow. They usually adhere to the side or underside of rocks that project from the water in flowing streams, on lake shores, or in rapids.