Studies on Norwegian Aphids - Norsk entomologisk forening

0,1 mm
Fig. 11. Platosternite of M. voigti Verhoeff '? from
Bavaria.
Figures of M.voigti & for comparison f.inst. in
Lohmander (1925, p. 22, Figs. 9-13).
Brolemann (1935) described for M.gallicum
a race helviorum from southern France, which
Ribaut (after Schubart 1963) declared a proper
species. From Brolemann's Figures it is the
posterior paragonopods in particular which are
different in helviorum and the nominate race.
In my material there is an especially large
variation In the size of the lateral branch on
the coxal projection. None of the posterior
paragonopods of M.gallicum in my collection
were of quite so dramatic appearance as in
M.g.helviorum (Brolemann 1935, Figs. 694 and
695). According to Brolemann there is also a
difference between helviorum and the nominate
race in the anterior paragonopods. Figs. 3
and 4 show the great variation within the
Norwegian material. Fig. 3 is nearly the same
as the nominate race (Brolemann 1935, Fig.
692), whereas Fig. 4 is very similar to M.g.helviorum
(Brolemann 1935, Fig. 693). For the
anterior gonopods (Fig. 5) the ratio of the
lengths of the coxal and sternal projections is
the same as for helviorum (Brolemann 1935,
Fig. 592), but the ratio for the length and
width of the sternaI projection is the same as
for genuinum (Brolemann 1935, Fig. 688). Brolemann
gives no differences for posterior gonopods.
Lohmander (1925) is of the opinion that the
variations of the gonopods of M.voigti, on the
basis of which Verhoeff (1938) established a
great number of races and varieties, are analogous
to the macrodactyle and brachydactyle
forms of the Craspedosoma species. The varia-
MICROCHORDEUMA GALLICUM NEW TO SCANDINAVIA
Hon which occurs within the Norwegian material
of M.gallicum should indicate a classification
into macro- and brachydactyle forms
for this species as well, but the quantity of &&
is at the moment too small to say anything
definite about this. Brolemann has no Figures
of the platosternite in helviorum.
Common to the Ascospermophora are the
papillae on the anal segment, the 3 pairs of
bristles dorsally on each segment and the lack
of poison glands. Ascospermophora are very
dependent on a high humidity. They can tolerate
low temperatures to a far greater extent
than other diplopods but are very sensitive to
higher temperatures. As a result of their lowtemperature
tolerance most ascospermophores
are active during autumn and spring (cf. list
of finds). Copulation has been observed in
April and October (Schubart 1934).
Microchordeuma gallicum is described from
the north-west of France (Latzel 1884). Schubart
(1934) mentions it from Germany, west
of the Rhine, Belgium, the Netherlands (in
Talpa nests) and Switzerland (up to 2,000 m
above sea level underneath stones). Eason
(1957) describes it from Great Britain (Wales,
Caernarvonshire, 1 '? + 1 & in garden leaf-litter).
Schubart (1963) makes a further report
from Luxembourg.
The find at Seim is therefore the northernmost
locality reported for Microchordeuma
gallicum. It has not been found in Denmark or
Sweden.
Whether the animals from Norway have a
synantropic distribution is not clear as yet. If
their immigration to Norway has been synantropic
they have had enough time to occupy
their natural biotopes.
M.voigti Verhoeff has a synantrope distribution
in the south of Sweden (Lohmander 1925)
and in Jutland, Denmark (Lohmander 1957).
It orginates in the German Jura (Verhoeff
1918) and has spread within Germany on shipments
of earth and plants (Verhoeff 1932).
Schubart (1934) reports it from northern Switzerland,
and also one find in Czechoslovakia.
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