Although many aquatic macroinvertebrates are affectionately called “stream bugs,” the Hemiptera comprise the only “true bugs” of all insect orders. Both adults and larvae can be aquatic and occupy the same habitat, with both stages distinguished by piercing-sucking mouthparts that may consist of an elongate beak or short cone jutting from their front of the head and projecting back. Hemimetabolous true bug larvae exhibit wing pads on the thorax, which will become one pair of soft hind wings one pair of hemielytra. Most aquatic true bugs act as piercer-predators as both larvae and adults, meaning they seize their prey with their front legs before using their specialized mouthparts to pierce and suck their meal clean.
Commonly all insects are called “bugs”; however, the term “bug” actually refers to a specific order of insects, the Hemiptera, or so-called “true bugs.” Not all members of the group are aquatic, however there are nearly 5,000 aquatic or semiaquatic species worldwide. They are hemimetabolous, meaning that the life cycle does not have a pupal stage, and adults and larvae look very similar, except for the lack of wings when immature (wing pads may be present). True bugs can almost always be distinguished from other insects by the presence of a pointed beak or rostrum; this is a set of piercing-sucking mouthparts, usually long, that is held beneath the body (ventrally) when not feeding. These insects are often herbivores, feeding on plant fluids, or predators that inject their prey with digestive enzymes which liquefy the tissues so that they can be easily sucked back up through the straw-like mouth.
+ Expanded Character List
Adults: With or without wings. If wings present, forewings typically leathery or hard basally and translucent and flexible apically. Nymphs: With or without wing pads. Segmented legs present. Mandibles hidden within needle-like beak in adults and nymphs.
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