birch catkin bug

not listed

NNR - Unranked

not listed

Birch catkin bug is a small seed bug. It occurs in Europe, eastern Asia, and North America. Based on the number of reported sightings, it is relatively uncommon in Minnesota. However, it is probably under-reported due to its small size.

Adults are ⅛″ to 3⁄16″ (4.5 to 5.5 mm) long, reddish-brown, and fairly hard-bodied.

The head is longer than wide, projected forward, and densely covered with small punctures (punctate). The beak-like part of the head containing the mouth parts (rostrum) has four segments. It is short, slender, and projects downward and forward when sucking plant juices. It is tucked into a groove on the underside of the thorax when not in use. The antennae are much longer than the head but much shorter than the body. They have four segments beyond the short basal segment (scape). They are widened at the tip (clubbed). The first and fourth segments are darker than the second and third. There are two large compound eyes on the sides of the head and two small simple eyes (ocelli) on the top of the head.

The exoskeletal plate covering the thorax (pronotum) is densely punctate.

There are two pairs of wings, and they are held flat over the body when at rest. The front wings (hemelytra) are longer than the hind wings and much longer than the body. The exoskeletal plate between the wing bases (scutellum), is large, triangular and reddish-brown at the tip. The hemelytra have a thickened part at the base and a thin, membranous, mostly transparent part at the tip, with a clear dividing line between the two. The thickened part is comprised of narrow area (clavus) behind the scutellum when the wings are closed and the broad marginal area (corium). At the end of the corium there is a small but distinct triangular area (cuneus). The clavus has three rows of punctures. The corium is clear or yellowish and has several dark spots.

The legs are mostly reddish-brown. The last part of the leg (tarsus), corresponding to the foot, is brownish-black and has 3 segments. The last tarsal segment has a claw at the tip. There is a pad at the base of each claw.

Nymphs look like wingless adults.

Total Length: ⅛″ to 3⁄16″ (4.5 to 5.5 mm)

One generation per year (in Ontario)

Adults overwinter within birch catkins in leaf litter on the ground. They emerge in early spring and lay eggs in June.

Seeds of birch trees and shrubs

Sources

24, 27, 29, 30, 82.

Location: Woodbury, Minnesota