A water boatman, Corixa sp. (Hemiptera: Corixidae). Photo by Drees.
Common Name: Water boatman
Order: Hemiptera
Scientific Name: Corixa sp.
Description: Water boatmen are somewhat flattened and elongate in shape. They have the hind two pairs of legs fitted with hairs and the tarsi of the hind legs is scoop or oar-shaped which allows them to swim. Adults range in length from 3/16 to 3/8 inch (3 to 11 mm) long and are usually dull colored and often mottled.
Water boatmen are the largest group of aquatic true bugs. They are sometimes confused with backswimmers (Hemiptera: Notonectidae) because they have the same general shape. However, backswimmers swim upside down in the water and are colored with the wings lighter than the leg area. Adults are relatively small and soft bodied so they do not preserve well on insect pins.
Life Cycle: Immatures are similar to the adult and share the habitat.
Habitat, Food Source(s), Damage: Their sucking mouthparts are modified to allow some chewing. Water boatmen often swim in open water. They can be seen in groups or clusters swimming through a pond. They feed on plant material, including algae. Water boatmen can be collected with aquatic nets.
Pest Status: May occasionally be a problem when numerous in ponds. They are beneficial because they are an important part of the diet of fish; medically harmless.
Management: None, these are considered beneficial insects
For additional information, contact your local Texas A&M AgriLife Extension Service agent or search for other state Extension offices.
Literature: McCafferty 1981.