Acanthocinus griseus is widespread species of coniferous, mainly spruce forests of all categories. Larval development under bark of weakened, uprooted, freshly felled or even standing trees with fresh phloem. Data on the development of larvae in completely dry wood is not based on reality, the wood must contain at least a little moisture. The species usually attacks wood that has already been attacked by bark beetles (particularly by Ips typographus and Ips duplicatus, less often Pityogenes chalcographus). A. griseus generally prefers trunks of larger diameter, but infests also relatively thin branches. The larvae create during feeding flat galleries, clogging them with frass and later with splinters, or toss feeding residues out through the holes. Pupation in a shallow flat pupal cell 10-15 mm below the surface of the wood, less often directly under the bark, or directly in a thick bark (in Pinus). The entrance/exit holes are oval, clogged with ca 6 mm long splinters. Life cycle (with overwintering larvae) one or two years, apparently according to local and temperature conditions. Adults, emerging from May to August, are during daylight hidden on the wood underside, in crevices and under bark scales, rarely running over the bark. Crepuscular/nocturnal species, often attracted to light.

Body length:	8 - 13 mm
Life cycle:	1 - 2 years
Adults in:	April - August
Host plant:	mainly in coniferous trees (Pinus, Picea, Abies), reported from oak (Quercus)
Distribution:	Europe, Russia, Asia Minor

The depicted living beetles were reared from larvae found in a dead silver fir (Abies alba) in Křivoklátsko Protected Landscape Area (Central Bohemia, Czechia). The mounted beetles were reared from larvae found under bark of a fallen Norway spruce (Picea abies). The larvae were collected in Bělečko near Hradec Králové (East Bohemia, Czech Republic).

Collected by Miroslav Polcar and M.Hoskovec