Anthropogenic dispersal of a snakefly (Insecta, Neuropterida) - a singular phenomenon or a model case in Raphidioptera?
Document type:
Article
Author(s):
Aspoeck, Horst; Aspoeck, Ulrike; Gruppe, Axel; Sittenthaler, Marcia; Haring, Elisabeth
Abstract:
The Mediterranean snakefly Raphidia mediterranea H. Aspock, U. Aspock &
Rausch, 1977 - known from many parts of the Balkan Peninsula, several
Aegean islands, southern parts of Italy, northwest of Anatolia and a few
localities in Eastern Europe, yet not recorded in Central Europe - was
surprisingly found with an astoundingly high population density on
bushes in the yard of an old farmhouse at a comparatively high altitude
(800 m) in Upper Austria, north of the Danube River, in 2013. This
spectacular phenomenon was again observed in the following years (2014,
2015, 2016, 2017), and in 2016 the suspicion that the larvae develop in
the straw of the thatched roof of the farmhouse could be confirmed by
findings of larvae, pupae, and exuviae. It is most likely, that the
occurrence of this Raphidia species in Austria is to be traced back to a
human-caused introduction at some point in time. It remains, however,
unknown when and specifically how this event might have occurred.
Morphologically no substantial differences were found between specimens
from Greece, Italy and Upper Austria. In addition, the genetic
uniformity (using 3 genes: cox1, cox3, and 28S) of the populations was
verified. This supports an earlier hypothesis that the occurrence of the
species, as well as that of R. mediterranea in Italy, Anatolia and
perhaps elsewhere, may be related to importation of goods involving wood
or soil.
A molecular genetic analysis of several Raphidia species confirmed the
present morphology-based concept of their systematic position.
The means of dispersal of Raphidioptera are largely unknown. We do not
know of any other similar cases of anthropogenic dispersal of a
snakefly, but it cannot be excluded that human activities may have
played a greater role in the dispersal of Raphidioptera than previously
assumed. Phylogenomic studies would therefore be promising to solve some
of these questions.