Brachypterus glaber (Newman, 1834)
POLYPHAGA Emery, 1886
CUCUJOIDEA Latreille, 1802
BRACHYPTERUS Kugelann, 1794
This is a generally common Palaearctic species distributed from the north of Scandinavia to the northern Mediterranean borders and from Portugal east to Finland and the Caspian Sea. Unlike the Holarctic B. urticae this species is absent from the Nearctic region and most of Asia. In the U.K. it is locally common throughout England and Wales and there are scattered records from Scotland. The lifestyle is much the same as that of B. urticae with both adults and larvae feeding on nettle flowers; the larvae develop within the flowers and seed pods and pupation occurs in the soil beneath the stems. Adults appear on nettles from early May, when they can be seen mating, and later disperse to feed on a range of flowers, more especially umbels, in a wide range of situations including parkland and urban gardens. They generally occur in smaller numbers than B. urticae and often together with that species as well as among numbers of other flower feeders e.g. Meligethes and Anaspis. Members of this genus soon become obvious in the field; the form of the head and the exposed abdomen are distinctive, and while the metallic lustre and pale appendages of B. urticae are generally obvious, they will generally need to be examined under the microscope to be sure.
1.8-2.0mm. Upper surface shiny black without a metallic reflection; less strongly and more densely punctured and with longer pubescence than B. urticae. Appendages black although the front legs may be dark brown. The head is strongly rugose and dull, in contrast to the pronotum, the clypeus dull with sparse and fine pubescence anteriorly. Pronotum rounded and weakly sinuate before the curved hind angles, the hind margin almost straight. The lateral margins are strongly bordered, the basal margin only weakly so. Elytra quadrate with the surface sculpture and pubescence as the pronotum. First visible tergite produced backwards laterally. Basal segments on all tarsi strongly lobed and all claws with a strong tooth at the base.
Brachypterus glaber 1
Brachypterus glaber 2
© Lech Borowiec http://www.cassidae.uni.wroc.pl/Colpolon/index.htm
Antennal club compact and abrupt.
Pygidium only exposed beyond elytra.