Damsel Bugs / Home and Landscape / UC Statewide IPM Program (UC IPM)

Hosts or Prey

Predaceous on a wide variety of insects of various sizes

Identification

Damsel bugs have an elongate body that tapers toward the front. The head is narrow with bulging eyes, long antennae, and tubular-sucking mouthparts. The legs are long and the front pair are slightly swollen with inconspicuous spines. Adults and nymphs can move rapidly when disturbed or stalking prey.

Adults commonly are brown, gray, reddish, or yellowish. They are about 1/6 to 1/2 inch (4–13 mm) long, varying by the species.

Nymphs commonly resemble adults of the species in coloration and shape, but are smaller and wingless. Developing wings are visible as oblong swellings (wing pads) partially covering the abdomen of older nymphs.

Eggs are oblong and flattened on top. Females insert eggs into soft tissue of plants with only the circular, flat opening (operculum) visible.

Lookalikes

Damsel bugs can be distinguished from most other true bugs (Heteroptera) by the presence of multiple, elongated cells (translucent areas segregated by veins) around the outer margin (tip) of the front wings. Similar-looking minute pirate bugs (Anthocoridae) have no obvious veins or cells near the forewing tips. Plant bugs (Miridae) have one or two, closed cells in the outer portion of each front wing.

Life Cycle

True bugs (Heteroptera) develop through three life stages. Eggs hatch into nymphs, which develop through five increasingly larger instars. The last instar develops into an adult without any pupal stage in between.

Egg to adult development requires 1 to 2 months during warm weather. There are 2 or more generations per year. Overwintering is mostly as adults in protected places.

Habitat

Damsel bugs occur in row and tree crops and gardens and landscapes. Adults and nymphs feed through needlelike mouthparts, sucking the body fluids of their prey. They feed on aphids, beetles, caterpillars, mites, thrips, various true bugs such as Lygus species, and sometimes on other natural enemies and prey larger than themselves. Damsel bugs also feed harmlessly on plants.

Species

At least nine species occur in California, including the common damsel bug, Nabis americoferus, and western damsel bug, Nabis alternatus. There is disagreement whether certain others should be considered species of Nabis or named otherwise, including Himacerus major, Hoplistoscelis heidemanni, and Pagasa confusa.