Parent Bug

Elasmucha grisea can reach a length of 6.5–8.8 millimetres (0.26–0.35 in). Males are smaller than females. These medium-sized shield bugs are usually brown-reddish, but there are also gray (hence the Latin species name grisea) and green-brown specimens. The connexiva are black and white. The upper side is covered with several dark dots. The scutellum usually shows an evident black patch. The ventral face is largely punctuated with black. The lateral corners of the pronotum are simply beveled. The front corners of the pronotum show a more pronounced tooth. Antennae are blackish in the male, dark brown in the female. This species, like other parent bugs, possesses metathoracic and abdominal glands, which discharge a foul smelling secretion. This secretion is used to deter potential enemies and is sometimes released when the bug is disturbed.

Elasmucha grisea is a rather common and widespread species present in most of Europe.

Adults of E. grisea can be found all year around. In fact, this species overwinters as an adult. Mating occurs in the spring and new adults can be found in August. These shield bugs feed on various woody plants, preferably on birch (Betula sp.), but also on alder (Alnus sp.), beech (Fagus sp.), holly (Ilex sp.), spruce (Picea sp.), etc. Like most shield bugs, E. grisea and other parent bugs suck plant sap and require symbiotic bacteria for their digestion. They obtain symbionts at an early age: the mother covers her eggs with bacteria so that the nymphs ingest them as they feed on the egg case. Both adults and nymphs readily feed on developing seeds, and breeding individuals can be observed on host plants with many young catkins. However, they seem to avoid trees with a high predation risk.