Corresponding author: Adalgisa Guglielmino (
Academic editor: Dominique Zimmermann
A new species,
The genus
The existence of a taxon slightly different from
The aim of the present paper is to describe the new taxon,
Measurements were made by using a Zeiss Stemi SV 11 Stereomicroscope with ocular micrometer. A camera lucida attachment was used for the drawings; pencil sketches were subsequently copied on cardboard by means of a light table and elaborated with drawing ink. Photographs were prepared with a digital camera Canon Eos70D supplied with lens 105 mm f/2,8 Macro Canon, extension tube 25 mm Canon, and ring flash Nikon SM-2.
We examined specimens of the following collections:
Institute of Zoology, National Academy of Sciences of Ukraine (Kiev)
Naturhistorisches Museum, Basel, Switzerland
Museo Cantonale di Storia Naturale, Lugano, Switzerland
Muséum d’Histoire Naturelle, Genève, Switzerland
Muséum National d’Histoire Naturelle, Collection Ribaut, Paris, France
Zoological Institute of the Russian Academy of Sciences, Saint Petersburg, Russia
Museum für Naturkunde, Berlin, Germany
Moravian Museum, Brno, Czech Republic
Museo Civico di Storia Naturale, Trieste
Museo di Storia Naturale, Collection Servadei, Verona
Department of Agricultural and Forestry Sciences, University of Tuscia, Viterbo, Italy (collection Adalgisa Guglielmino)
Department of Biological, Geological and Environmental Sciences, sec. Animal Biology, University of Catania (Collection Vera D’Urso)
Private collection Ilia Gjonov, Sofia, Bulgaria
Private collection Christoph Bückle, Tübingen, Germany
Private collection Gabrijel Seljak, Nova Gorica, Slovenia
Private collection Kees den Bieman, Ulvenhout, Netherlands
Private collection Werner Holzinger, Graz, Austria
The material of the Servadei collection is presently not available, but was checked and listed by our colleague Manfred Asche (Berlin) some years ago.
The locality numbers in parentheses in the examined material of the collection Guglielmino
For a detailed list of the material please see Suppl. material
Body length: 2.45–2.90 mm (brachypterous males), 3.85–4.20 mm (macropterous males), 2.90–3.40 mm (brachypterous females), 4.30–4.50 mm (macropterous females). Head length: 0.20–0.28 mm (males), 0.26–0.30 mm (females). Head width including eyes: 0.78–0.92 mm (males), 0.88–0.96 mm (females). Pronotum length: 0.20–0.25 mm (males), 0.22–0.26 mm (females). Mesonotum length: 0.40–0.50 mm (brachypterous males), 0.58–0.64 mm (macropterous males), 0.44–0.52 mm (brachypterous females), 0.66–0.80 mm (macropterous females). Length of fore wings from shoulder to wing tip: 1.15–1.48 mm (brachypterous males), 3.15–3.50 mm (macropterous males), 1.24–1.48 mm (brachypterous females), 3.65–3.75 mm (macropterous females).
In size, coloration and shape very similar to
Coloration. Males (Figs
Genital morphology. Males (Figs
The pygofer and aedeagus morphology (in males), e.g. width of the aedeagus, number of the aedeagal spines (Figs
Transitional forms between
Main differences to
(Fig.
Outline map of the distribution of the species of the
The species was mostly found from beginning of June until end of August, but one record from April (340m) indicates that the taxon may be bivoltine in lowlands. In mountain regions it has apparently only one generation.
Type material deposited in Department of Agricultural and Forestry Sciences
(For further material of this taxon see Suppl. material
We examined specimens from Finland (Fig.
Specimens from northern Poland display characters as those of other Central European regions, but have a small preapical tooth on their styles (Fig.
The pygofer and aedeagus morphology (in males), e.g. width of the aedeagus, number of the aedeagal spines (Figs
The pygofer morphology is illustrated in Figs
Females are undistinguishable from
Remark: The record of
Unfortunately, our knowledge on both taxa from the Caucasus region is based only on very few specimens, thus the range of variability in these taxa is unknown.
Besides the different shape of the genital styles in
For the explanation of this situation we may go back to a period when the areas of the ancestors of both recent taxa were separated and speciation was in progress.
But before we have to make some considerations: The asymmetry of the aedeagus in
The aedeagus morphology in
A striking parallel case is to be mentioned in another delphacid genus,
Chiral dimorphism is observed also in other groups of insects as in the mantid genus
Preliminary remark: The existence of supposed hybrids between
In southwestern France
In these supposed hybrid populations, aedeagi with phallotreme on the left side (Fig.
We may mention in this context a similar case in the
There is little doubt that the division of
We suppose that the area of the common ancestor of both taxa was restricted during a cold climate period, and finally divided in two separate areas, which was the basal situation for a speciation process towards the presently observed two taxa. During a following warmer period both groups may have extended their areas, and developed a hybrid area where they got in contact with each other.
The present disjunct distribution of
One scenario is the colonisation of the Iberian Peninsula directly from Italian mainland or, less probably, viceversa via drifted macropterous specimens crossing the Mediterranean Sea. Generally macropterous specimens are found quite frequently within
In our opinion another scenario is more probable: we suppose that the taxon in former times had a continuous distribution in the Westmediterranean region (and possibly not only there) including at least southern France. A following restriction of its area due to climatic changes may have resulted in the division in two separated areas on the two Peninsulas, respectively.
Finally,
In the central part of the Alps
It is quite evident that
The small preapical tooth in two
For a better understanding of the distribution of
Furthermore, it would be interesting to compare morphological data, gathered in the presented paper and in future studies, with bioacoustic and molecular data, in order to get further hints on how the present disjunct area of
Crossing experiments between populations from the latter region, and the examination of the offspring of left side phallotreme and right side phallotreme males would as well furnish interesting results.
For generous help in the loan of material from many collections we are very grateful to the following colleagues: Manfred Asche (Germany, Berlin), Daniel Burckhardt (Switzerland, Basel), Kees den Bieman (Netherlands, Ulvenhout), Ilia Gjonov (Bulgaria, Sofia), Vladimir Gnezdilov (Russia, St. Petersburg), Werner Holzinger (Austria, Graz), Tomasz Klejdysz (Poland, Poznań), Pavel Lauterer (Czech Republic, Brno), Lucia Pollini (Switzerland, Lugano), Alexander Putchkov (Ukraine, Kiev), Gabrijel Seljak (Slovenia, Nova Gorica), Adeline Soulier-Perkins (France, Paris), Valeria Trivellone (Switzerland, Bellinzona), John Hollier (Switzerland, Genève).
Many thanks to Massimo Vollaro (University of Tuscia, Viterbo, Italy) for the production of macrophotographs and his assistance in preparing the figures.
We acknowledge the Museum für Naturkunde, Berlin for waiving the authors fees.
Detailed list of study materials
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