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Anaerobiosis in some alpine Coleoptera
LAURITZ S0MME
Snmme, L. 1974. Anaerobiosis in some alpine Coleoptera. Norsk ent. Tidsskr. 21,
155-158.
Anaerobiosis was studied in adult Coleoptera overwintering in the mountains at
Finse, South Norway. No mortality occurred in Lepyrus arcticus Payk. after 50 to
60 days in nitrogen at O0 C, or in Byrrhus pilula L. and Otiorrhynchus dubius
Strnm kept up to 120 days under these conditions. About 80°/o of Pelophila borealis
Payk. survived 156 days. During anoxia considerable amounts of lactate
accumulated in the haemolymph of al1 species.
Lauritz Snmme, Zoological Institute, University of Oslo, P. B. 1050 Blindern,
Oslo 3, Norway.
At Finse, on the mountainous plateau of
Hardangervidda in South Norway, severa1
species of Coleoptera are found in a sedimentation
flat at 1200 m a.s.1. (0stbye 1969).
Some species, like the carabid beetle Pelophila
borealis Payk., overwinter in the soil of
this flat (0stbye & S~imme 1972). The flat
has been deposited by the adjacent river,
which partly originates from the glacier
Hardangerjnkulen. The vegetation of the
flat has been described by Lien et al. (1974).
Due to flooding of the river, the overwintering
sites of the beetles may be covered by
water, and the beetles subsequently enclosed
by ice. The survival of P. borealis under
these conditions depends on their anaerobic
metabolism. As described by Conradi-Larsen
& Snmme (1973a, b) almost al1 adults of this
species survived 8 to 127 days in nitrogen at
0' C. During anaerobiosis large amounts of
lactate accumulated in their haemolymph.
Severa1 other species of Coleoptera overwinter
in the sedimentation flat. Like P.
borealis they may experience serious oxygen
deficiences when the flat is covered by ice.
Thus anaerobic metabolism may be of vital
importance to other beetles as well. The purpose
of the present investigation was to study
the effect of anaerobic conditions on various
species of adult beetles from this particular
habitat.
METHODS
Adult beetles were collected in September
1973. While P. borealis appeared in large
numbers, other species were less common.
The beetles were put in plastic boxes filled
with soil and placed in the ground at the
overwintering sites (Conradi-Larsen Pc Snmme
1973b). In December 1973 and January 1974
the boxes were removed and the beetles
placed in alass tubes filled with nitroaen as
hescribed -by Conradi-Larsen & gnmme
(1973b). The tubes were stored at O0 C, which
approximately corresponds to the soil temperature
at the overwintering sites of the
beetles. After various time intervals the
tubes were broken and the survival rates of
the beetles recorded. Apparently normal
beetles were counted as alive, beetles moving
but unable to walk as moribund. and those
without movements as dead.
The content of lactate in the haemolymph
was measured in some beetles after removal