Norwegian Journal of Entomology - Norsk entomologisk forening

Norw. J. Entomol. 53, 5-9, 22 May 2006
The overwintering of Gonioctena pallida L.
(Coleoptera, Chrysomelidae) in the alpine zone at Finse,
Norway.
Ole J. Lønnve, Jostein-André Nordmoen & Lauritz Sømme
Lønnve, O.J., Nordmoen, J.A. & Sømme, L. 2006. The overwintering of Gonioctena pallida L.
(Coleoptera, Chrysomelidae) in the alpine zone at Finse, Norway. Norw. J. Entomol. 53, 5-9.
In the low alpine zone at Finse, Norway, Gonioctena pallida overwinters as adult in soil and litter
underneath shrubs of Salix spp. Larvae are present on Salix during the summer, and pupate in the litter
in the autumn. Due to a thick cover of snow, winter temperatures at the overwintering sites rarely
drops more than 1 or 2 °C below zero. In the laboratory, adult beetles survived 314 days at 2 °C, and
another 420 days at this temperature following a short period of feeding. The adults also survived
more than 8 months at –3 °C and more than six months at –6 °C. In contrast, all pupae died after two
months at 0 °C. Mean supercooling points of adult beetles stored at 0 °C remained close to –10 °C
during the winter. It is concluded that G. pallida is sufficiently cold hardy to survive alpine winter
conditions in the adult stage. Apparently, the species has a one-year life cycle.
INTRODUCTION
Key words: Gonioctena pallida, Coleoptera, Chrysomelidae, overwintering, supercooling points
Ole J. Lønnve, Natural History Museum, University of Oslo, P.O. Box 1172 Blindern, N-0318 Oslo,
Norway. E-mail: o.j.lonnve@nhm.uio.no
Jostein-André Nordmoen, Hesteskoen 38 A, N-2050 Jessheim, Norway.
E-mail: Jostein.Nordmoen@sylinder.no
Lauritz Sømme, Department of Biology, University of Oslo, P.O. Box 1066 Blindern, N-0316 Oslo,
Norway.
The chrysomelid beetle Gonioctena pallida L.
inhabits the lower alpine zone of the Scandinavian
mountain chain but is also widely distributed in
the lowlands of Fennoscandia, Siberia and Central
Europe (Silferberg 1989, 2004). Species of the
genus Gonioctena are specialist herbivores. Both
larva and adult feed on the same host plants, which
include Salix, Corylus and Quercus (Hansen
1927). G. pallida is facultative vivipar (Bontems
1988) and the life cycle is completed in one year
(Axelsson et al. 1974a,b). In the lowland, the
fully developed 4. instar larvae leave their host
plants and pupate in the ground. The pupae hatch
in the autumn and following a period of feeding,
the adults overwinter in soil and litter. Like
chrysomelids in general, their power of dispersal
appears to be limited. Adults are rarely seen
flying, although capable of doing so (Richards
& Waloff 1961, Mason & Lawson 1982). More
recently, phylogeographical studies of a regional
population of G. pallida in Central Europe showed
that the presence of several effective barriers
prevents recurrent gene flow within the studied
area (Mardulyn 2001).
In the low alpine zone at Hardangervidda,
Norway, G. pallida feeds on several Salix spp., in
particular on Salix lanata and to a lesser extent on
Salix glauca and Salix lapponum (Nordmoen &
Lønnve 1996).
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