Apionidae Schönherr, 1823

Christoph Germann, Sofia Wyler & Marco Valerio Bernasconi, 2017, DNA barcoding of selected alpine beetles with focus on Curculionoidea (Coleoptera), Revue suisse de Zoologie 124 (1), pp. 15-38 : 17

Family Apionidae Schönherr, 1823

Genera Aizobius Alonso-Zarazaga, 1990

Hemitrichapion Voss, 1859 &

Osellaeus Alonso-Zarazaga, 1990

The Apionidae group is only weakly (NJ) or insufficiently (ML <50%) supported in our analyses ( Fig. 1 , Supp. 1) but, on the contrary, the monophyly of the genera (i. e. Aizobius , Hemitrichapion , and Osellaeus ) found strong support in both the ML and NJ tree.

The genus Osellaeus is represented with three strictly subalpine-alpine taxa in the western alpine arch – O. bonvouloirii baldensis (Bellò, Meregalli & Osella, 1980) on Monte Baldo, O. bonvouloirii s. str. (Ch. Brisout, 1880) in the central and western Alps and O. bonvouloirii occidentalis Germann, 2010 in the Vercors ( Germann & Szallies, 2011). We included three Swiss populations of the nominal subspecies, but the third one from the Valais did not produce a positive PCR. The one from Uri (Brisen) and the other from Fribourg (Kaiseregg) are from localities just 91 km distant from each other. As O. bonvouloirii is a flightless, and restricted to its alpine habitat and thus a very low mobile species, the detected differences (K2 distance: 0.059; Table 1) are well explainable.

Three other Apionidae were included, of which Mesotrichapion punctirostre (Gyllenhal, 1839) did not give a result. The species with the widest distribution reaching from Central Asia to France is Aizobius sedi (Germar, 1818). However, the species is restricted to xerothermic places and unable to fly, this may explain for the rather large intraspecific genetic distance (0.027) between the two samples taken 300 km from each other. The third species sampled is Hemitrichapion waltoni (Stephens, 1839), recorded from Hungaria to France. The samples taken at localities separated by a distance of 340 km, a species which has normally developed hind wings and is the most mobile of all species included and may therefore show the lowest genetic distance of all Apionidae included (0.011).

These results underline once more the importance of the need for conservation of isolated populations of flightless, ecologically highly specialised and thus low mobile endemic species.

Figures

Fig. 1. Best Maximum Likelihood tree as selected by MEGA) based on COI sequences of 142 samples of Curculionoidea (Chrysomelidae obtained by using MEGA 6. Values (over 50 %) of bootstrap support from 100 nodes.