Fróðskaparrit - 01.01.2009, Page 121

PLANTUVØLIR OC VØLAMÍGCJ (DIPTERA: CECIDOMYIIDAE) (FØROYUM
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Results
Only ten gall-causing and gall-associated
organisms occurring on seven host plant
species belonging to seven plant families
were found during our seven-days searching
for galls in the Faroe Islands (Table 1). Of
these seven galls were caused by gall-causing
organisms (two species of Cecidomyiidae,
two species of Eriophyidae and three species
of Fungi) and larvae of three other gall midge
species were found during microscope exa-
mination of galls and leaves.
Table I. List of hosc plants and gall-causing and other
organisms found in Tórshavn on the island Streymoy
in the Faroe Islands in 2005
Host plant species Call-causing organism
Acer pseudoplatanus Aceria pseudoplatani
Galium anisophyllum Aculus anthobius
Juniperus communis Oligotrophus juniperinus
Ribes rubrum Cronartium ribicola
Salix phylicifolia Melampsora caprearum Mycodiplosis melam- psorae
Sorbus aria Contarinia floriperda Clinodiplosis cilicrus Feltiella acarisuga
Viola riviniana Puccinia violae

Annotated list of species
Gall midges (Diptera: Cecidomyiidae)
Contarinia floriperda Rúbsaamen, 1917
Larvae develop in flower buds of Sorbus aria L.
(Rosaceae) which become swollen and not develop
into flowers (Fig. 1). In July the larvae leave attacked
buds and fall to the soil and enter the soil where they
hibernate until spring of the following year. At the time
of collecting in August 2005, the galls were without
larvae. Sorbus aria is not native to the Faroe Islands.
Locality^Streymoy, Tórshavn, private garden, 6.8.2005.
Bistribution. C.floriperda is a European species that is
relatively rare (Skuhravá, 1997). This species was
Fig.1 . Swollen flower bud (above on the right), the gall
of Contarinia floriperda on the flower bud of Sorbus
aria. Photograph by Václav Skuhravy.
originally described based on adults reared from
swollen flower buds of Sorbus aucuparia L. in Germany
(Rubsaamen, 1917). The galls of this species have been
found on this host plant species subsequently in
Britain (Bagnall and Harrison, 1921), Russia (Dombrov-
skaja, 1936), Sweden (Wahlgren, 1944), the Nether-
lands (Alta, 1946), Latvia (Spungis, 1979), Czech Repu-
blic (Baudys, 1923), Bulgaria (Skuhravá et al„ 1991),
Austria (Skuhraváand Skuhravy, 1995), Italy (Skuhravá
et al„ 2002) and Denmark (Skuhravá et al„ 2006) (Fig.
2). The galls of C.floriperda on the host plant species
Sorbus aria were found relatively rarely, only in Britain
and in the Czech Republic. The findingof C.floriperda
in the Faroe Islands is the most northern occurrence
in Europe.
Vertical occurrence: C. floriperda occurs over a large
altitudinal span including sites near the sea level in the
island of Læsø in Denmark and up to 2200 m a.s.l. in
the Alps in northern Italy (Skuhravá et al„ 2002; 2006).
Oligotrophus juniperinus (Linná, 1758)
Larvae cause terminal or axillary bud galls on branches
of Juniperus communis L. (Cupressaceae) (Fig. 3). The