Photo © M.Hoskovec
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| Body length: | 6 - 8 mm |
| Life cycle: | 1 - 2 years |
| Adults in: | May - July |
| Host plant: | chiefly poplars (Populus tremula, nigra and alba) |
| Distribution: | Europe |
The preferred host plant of this species in Central Europe is white poplar (Populus alba).
However, growths of this tree have dramatically declined in Europe and so have the populations of
the insect. Especially endangered are populations living in softwood lowland flood-plain forests
that are frequently subject to urbanisation or agricultural development. Fortunately, the
beetle is able to make do with an alternative host plant, namely aspen (Populus tremula),
and even follows this tree species to higher altitudes. In North Europe Populus tremula seems
to be the preferred host. Records from black poplar (Populus nigra) need revision in our
opinion. Larvae of this beetle feed subcortically in relatively thin dead branches of the host.
Shady and moist positions are preferred to sunny ones. The surface of the sapwood under the bark
is usually of a dark black colour. Only recently we have found out that this characteristic
colouration is caused by a fungus Encoelia fascicularis (Ake Lindelöw, personal communication,
2002). The larvae build a pupal cell directly under
the bark using a fibrous frass of a contrasting white colour.
The depicted beetles were reared from praepupae found in pupal cells built under the bark of
dead branches of white poplar (Populus alba). The praepupae were collected in Pouzdøany
and Bøeclav (South Moravia, Czech Republic).
Collected by M.Hoskovec and P.Jelínek
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