Gerris (Gerris) costae (Herrich-Schäffer, 1850)

Cianferoni, Fabio, 2019, Review of the aquatic Hemiptera from Cephalonia, with a checklist for the Ionian Islands, Greece (Heteroptera: Gerromorpha, Nepomorpha, Leptopodomorpha), Zootaxa 4576 (1) : -

Gerris (Gerris) costae (Herrich-Schäffer, 1850)

Material examined. Tzanata, stream, ca. 90 m a.s.l., 38.15069° N 20.73826° E (WGS84; uncertainty = 100 m), 23.VII.2018, F. Cianferoni, F. Graziani, F. Ceccolini leg., 1 ♂, 1 ♀ macr., CFCF.

General distribution. This is a Turano-European species (with extensions to the British Isles and Egypt) (see Saleh Ahmed & Gadalla 2005, Cianferoni & Mazza 2012, Damgaard et al. 2014).

Remarks. This is the first record of this species for Cephalonia. Although the Greek specimens were attributed to the taxon Gerris costae fieberi Stichel, 1938 ( Andersen 1995, Damgaard et al. 2014), the status and interpretation of the subspecies of G. costae (Herrich-Schäffer, 1850) are questionable because the diagnostic characters are ambiguous (see Cianferoni 2011 and Berchi et al. 2018a for further information). Therefore, the species is considered without subspecific assignment here.