Tettigettalna argentata (Olivier,1790)

Hertach, Thomas & Nagel, Peter, 2013, Cicadas in Switzerland: ascientific overview of the historic and current knowledge of apopular taxon (Hemiptera: Cicadidae), Revue suisse de Zoologie 120 (2), pp. 229-269 : 256-257

Tettigettalna argentata (Olivier,1790)

German common name: Silbrige Zikade ( Gogala, 2002)

French common name: La Cigalette argentée (e.g. Boulard, 1995)

DISTRIBUTION (Fig. 12)

Tettigettalna argentata (Olivier,1790) is asmall western Mediterranean cicada species that has been recorded in Spain and Portugal ( Sueur et al., 2004), France ( Puissant, 2006), northern Italy ( Ferrari, 1892; Schedl, 1973, 2000) and western Slovenia ( Gogala &Gogala, 1999). Some of the records of Schedl (1973) are situated not far from the Swiss border.The occurrence near Meran in the Italian South Tyrol had already been detected and described in the middle of the 19 th century ( Milde, 1865).

Tettigettalna argentata was discovered for the first time in Switzerland at Monte Caslano (TI, Lugano region) in 2007 ( Hertach, 2008). The species is abundant there with more than 30 males singing in 2008 .

No other populations have been found in Switzerland, but asingle and supposedly immigrant specimen was observed and recorded near San Vittore (GR) in the Mesocco Valley on 29 July 2011. Other current populations nearly reach the Swiss border in different regions: 1.7 km from the Poschiavo Valley (GR) ( Tirano , 2010 and 2011), 10.4 km from the Valais ( Doues , Aosta Valley ,2007) and 29.5 km from the Val Mustair (GR) ( Kastelbell-Latsch , Vinschgau , 2009). Immigration into the Poschiavo Valley might be expected in the near future .

ECOLOGY AND THREAT

The habitat at Monte Caslano consists of a very steep and rocky slope on limestone (Orno-Ostryon). Some areas of Monte Caslano are cultivated as dry meadows with bushes and small woods for habitat conservation by regional authorities ( Hertach, 2008). Maintenance or slight extension of these activities seems to be crucial for the conservation of this population of T.argentata .The Mesocco Valley specimen sang in intensively cultivated land with agarden, hedges and pastures, which is not typical for the species.

With only one established population the occurrence of this species in Switzerland is endangered. Nevertheless, the responsibility for the species is not high in the international context.

FIG.12 Distribution map of Tettigettalna argentata .