Gerris (Gerris) thoracicus Schummel, 1832

Berchi, Gavril Marius, Cianferoni, Fabio, Csabai, Zoltán, Damgaard, Jakob, Olosutean, Horea, Ilie, Daniela Minodora, Boda, Pál & Kment, Petr, 2018, Water striders (Heteroptera: Gerromorpha: Gerridae) of Romania with an update on the distribution of Gerris gibbifer and G. maculatus in southeastern Europe, Zootaxa 4433 (3), pp. 491-519 : 508-510

Gerris (Gerris) thoracicus Schummel, 1832

Material examined. ROMANIA: Alba County: Pănade [stream], 46°13ʹ26ʺN 23°57ʹ55ʺE, 248 m a.s.l., 09.vii.2014, leg. & det. P. Boda, 1 ♀ (ma) ( PBDH) . Bacău County: Comănești [pond], 46°24ʹ32ʺN 26°25ʹ32ʺE,

428 m a.s.l., 13.viii.2013, leg. A. Pintilioaie, det. G.M. Berchi, 1 ♀ (ma); idem [pond], 46°25ʹ38ʺN 26°26ʹ13ʺE, 492 m a.s.l., 14–15.vi.2013, leg. A. Pintilioaie, det. G.M. Berchi, 1 ♀ (ma). Bihor County: Băile 1 Mai [lake Pețea], 46°59ʹ50ʺN 22°00ʹ10ʺE, 163 m a.s.l., 05.v.2012, 1 ♀ (ma); Boga [pool], 1270 m a.s.l., 30.vii.1998 , leg. P. Šmarda, det. P. Kment, 2 ♂♂ (ma) ( NMPC); Padiș [pond], 46°35ʹ59ʺN 22°42ʹ09ʺE, 1243 m a.s.l., 23.vi.2013, 1 ♀ (ma); Tămășeu [stream], 47°12ʹ45ʺN 21°55ʹ36ʺE, 110 m a.s.l., 05.v.2012, 1 ♂ (ma); Vârtop [pond], 46°31ʹ18ʺN 22°39ʹ07ʺE, 1404 m a.s.l., 22.ix.2005 , leg. & det. D.M. Ilie, 1 ♂ (ma) 2 ♀♀ (ma) ( DISR). Bistrița-Năsăud County: Beclean [lake], 47°10ʹ30ʺN 24°13ʹ11ʺE, 252 m a.s.l., 11.viii.2013 , leg. & det. D.M. Ilie, 2 ♀♀ (ma) (DISR). Brașov County: Măieruș [stream], 45°54ʹ26ʺN 25°29ʹ27ʺE, 532 m a.s.l., 05.viii.2011, 1 ♂ (ma) 2 ♀♀ (ma) . Buzău County: Haleș [intermittent stream], 45°11ʹ54ʺN 26°33ʹ34ʺE, 207 m a.s.l., 31.vii.2012, 1 ♂ (ma) 7 ♀♀ (ma); Movila Banului [stream], 44°58ʹ06ʺN 26°39ʹ47ʺE, 74 m a.s.l., 21.vii.2014, 1 ♂ (ma) 2 ♀♀ (ma). Caraș- Severin County: Baziaș [stream], 44°49ʹ55ʺN 21°22ʹ13ʺE, 63 m a.s.l., 27.viii.2010, 1 ♂ (ma) 1 ♀ (ma); Rusca [pond], 45°08ʹ23ʺN 22°29ʹ37ʺE, 839 m a.s.l., 27.vi.2017, 1 ♀ (ma); Sichevița [stream], 44°42ʹ56ʺN 21°47ʹ54ʺE, 281 m a.s.l., 12.vii.2014, 1 ♂ (ma) . Cluj County: Caps [stream], 46°36ʹ58ʺN 23°17ʹ56ʺE, 827 m a.s.l., 08.vii.2014, leg. & det. P. Boda, 1 ♀ (ma) ( PBDH) . Constanța County: Crucea [stream], 44°31ʹ12ʺN 28°14ʹ00ʺE, 49 m a.s.l., 07.viii.2015, 1 ♀ (ma) . Dâmbovița County: Ghimpați [stream], 44°40ʹ27ʺN 25°48ʹ46ʺE, 131 m a.s.l., 21.vii.2014, 1 ♀ (ma); Mislea [stream], 44°50ʹ49ʺN 25°19ʹ28ʺE, 248 m a.s.l., 30.vii.2012, 3 ♀♀ (ma) . Dolj County: Vârtop [stream], 44°12ʹ28ʺN 23°18ʹ58ʺE, 141 m a.s.l., 27.vii.2012, 2 ♂♂ (ma) 1 ♀ (ma) . Harghita County: Corund [stream], 46°29ʹ59ʺN 25°09ʹ55ʺE, 522 m a.s.l., 11.vii.2014 , leg. & det. P. Boda, 2 ♂♂ (ma) 1 ♀ (ma) ( PBDH); Izvoru Mureșului [stream], 46°37ʹ25ʺN 25°44ʹ23ʺE, 870 m a.s.l., 27.vii.2011, 1 ♀ (ma) . Hunedoara County: Anineș [pond], 45°40ʹ33ʺN 23°15ʹ02ʺE, 1105 m a.s.l., 20.vii.2012 , leg. & det. H. Olosutean, 1 ♂ (ma) 1 ♀ (ma) (HOSR); idem [swamp], 45°40ʹ05ʺN 23°15ʹ20ʺE, 1041 m a.s.l., 20.vii.2012, leg. & det. H. Olosutean, 3 ♀♀ (ma) ( HOSR); Grădiștea de Munte [pond], 45°38ʹ01ʺN 23°13ʹ54ʺE, 577 m a.s.l., 20.vii.2012 , leg. & det. H. Olosutean, 3 ♀♀ (ma) ( HOSR); Merișor, 45°27ʹ22ʺN 23°13ʹ39ʺE, 593 m a.s.l., 19.viii.2010, 1 ♂ (ma) 1 ♀ (ma); Retezat Mountains [ lake Florica ] , 2090 m a.s.l., 24.vii.1999, leg. P. Šmarda, det. P. Kment, 2 ♂♂ (ma) 1 ♀ (ma) ( NMPC); idem [ Bucura ref.], 2200 m a.s.l., 23.iv.1999, leg. P. Šmarda, det . P. Kment, 1 ♀ (ma) ( NMPC); Valea Rea [channel], 45°39ʹ31ʺN 23°13ʹ33ʺE, 650 m a.s.l., 18.vii.2012 , leg. & det. H. Olosutean, 1 ♀ (ma) ( HOSR); Vața de Sus [stream], 46°09ʹ59ʺN 22°35ʹ47ʺE, 373 m a.s.l., 08.vi.2009 , leg. & det. D.M. Ilie, 1 ♀ (ma) (DISR). Iași County: Scobinți [stream], 47°24ʹ29ʺN 26°55ʹ40ʺE, 128 m a.s.l., 03.viii.2012, 2 ♀♀ (ma) . Maramureș County: Gutâi Mountains [pond], 47°41ʹ52ʺN 23°48ʹ48ʺE, 1063 m a.s.l., 01.v.2017, 1 ♂ (ma) . Mehedinți County: Orșova (= Jupalnic ), 30.iii.1967, leg. St. Negru, det . B. Kis, 1 ♀ (ma) (MGAB); Svinița [pond], 44°33ʹ05ʺN 22°02ʹ21ʺE, 121 m a.s.l., 19.viii.2012, 1 ♀ (ma). Mureș County: Sânger [stream], 46°33ʹ13ʺN 24°06ʹ44ʺE, 284 m a.s.l., 13.vii.2014 , leg. & det. P. Boda, 1 ♂ (ma) 2 ♀♀ (ma) (PBDH); Sântu [stream], 46°47ʹ29ʺN 24°38ʹ13ʺE, 375 m a.s.l., 29.iv.2017, 2 ♂♂ (ma) 1 ♀ (ma). Prahova County: Străoști [stream], 45°01ʹ51ʺN 26°13ʹ31ʺE, 136 m a.s.l., 30.vii.2012, 1 ♂ (ma) . Sălaj County: Ciumărna [stream], 47°07ʹ22ʺN 23°08ʹ49ʺE, 291 m a.s.l., 27.vi.2013, 1 ♂ (ma) . Satu Mare County: Drăgușeni [stream], 47°54ʹ51ʺN 23°04ʹ48ʺE, 132 m a.s.l., 26.vi.2013, 1 ♀ (ma) . Sibiu County: Sebeșu de Sus [pond], 45°37ʹ56ʺN 24°22ʹ11ʺE, 557 m a.s.l., 30.iii.2014, 1 ♂ (ma) 1 ♀ (ma) ; Sibiu [stream], 45°46ʹ40ʺN 24°08ʹ20ʺE, 440 m a.s.l., 13.x.2014, leg. & det. H. Olosutean, 1 ♂ (ma) ( HOSR) . Suceava County: Brodina de Jos [channel], 47°48ʹ56ʺN 25°23ʹ47ʺE, 674 m a.s.l., 05.v.2017, 1 ♂ (ma); Dolhasca [pond], 47°25ʹ51ʺN 26°37ʹ13ʺE, 217 m a.s.l., 30.vii.2011, 2 ♀♀ (ma); Dumbrăveni [stream], 47°20ʹ54ʺN 26°08ʹ10ʺE, 486 m a.s.l., 04.viii.2012, 1 ♀ (ma); Păișeni [pond], 47°25ʹ23ʺN 26°05ʹ25ʺE, 444 m a.s.l., 03.viii.2012, 1 ♀ (ma) . Timiș County: Brestovăț [stream], 45°51ʹ52ʺN 21°40ʹ05ʺE, 129 m a.s.l., 04.vii.2013, 3 ♂♂ (ma); Gătaia [stream], 45°25ʹ58ʺN 21°26ʹ24ʺE, 111 m a.s.l., 23.iv.2017, 1 ♂ (ma); Surducu Mic [stream], 45°46ʹN 22°06ʹE, 150 m a.s.l., 16.vi.2013, leg. F. Terzani & A . Bandinelli, det. F. Cianferoni, 1 ♂ (ma) ( MZUF) 1 ♂ (ma) 1 ♀ (ma) (CFC); Victor Vlad Delamarina [stream], 45°38ʹ16ʺN 21°54ʹ06ʺE, 134 m a.s.l., 22.iv.2017, 2 ♂♂ (ma).

Published records. Fuss (1853, 1862, as Hydrometra thoracica ), Horváth (1878, 1898a, b), Montandon (1885), Szilády (1908), Jaczewski (1934), Botoșăneanu et al. (1959), Sienkiewicz (1960, 1964), Benedek (1970), Cărăușu et al. (1972), Kis (1972, 1975, 1976), Schneider (1973), Kis & Davidescu (1994), Kis & Stănescu (1994), Kecskés (1997, 1999), Ilie (2001, 2003, 2007, 2014), Ilie & Davideanu (2002), Davideanu et al. (2004), Olosutean & Ilie (2007, 2008a, 2013a), Ilie & Olosutean (2009, 2012), Nicoară et al. (2009), Ilie & Ban-Calefariu (2010), Berchi et al. (2011), Berchi & Chimișliu (2015).

Remarks. In Romania, this species was identified at 49 sites at an elevational range of 49–2200 m a.s.l. ( Fig. 1 ). It was found from March to September in streams, channels, lakes, pools and ponds. All the specimens examined were macropterous.

In Austria and the Netherlands, G. thoracicus is usually bivoltine and macropterous, whereas in Hungary it was found as long-winged and multivoltine ( Vepsäläinen 1974a, Vepsäläinen & Nieser 1977). Mid-summer submacropterous specimens were reported from France, England, Finland ( Vepsäläinen 1974a), Mallorca and Denmark ( Damgaard 2006).

Distribution. Widely distributed across the Palaearctic Region, from Europe to northern India ( Andersen 1995, Damgaard et al. 2014). For the Romanian distribution, see Fig. 9 .

Figures

FIGURE 1. Boxplots representing the elevational distribution of Gerridae in Romania. Circles represent outliers and asterisks represent extreme values.

FIGURES 8–9. Distribution in Romania: (8) Gerris odontogaster (Zetterstedt, 1828); (9) Gerris thoracicus Schummel, 1832. Blank dots represent published records while solid dots represent records from this study.