Gerris (Gerriselloides) lateralis 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 : 498-499

Gerris (Gerriselloides) lateralis Schummel, 1832

Material examined. ROMANIA: Bihor County: Padiș [lake], 46°34ʹ49ʺN 22°41ʹ00ʺE, 1150 m a.s.l., 19.viii.2005, leg. D.M. Ilie, det. G.M. Berchi, 1 ♂ (ap) 1 ♀ (ap) ( DISR). Caraș-Severin County: Semenic Mountains [stream], 45°07ʹ34ʺN 22°02ʹ55ʺE, 1113 m a.s.l., 08.iv.2014, 1 ♂ (ma). Covasna County: Mesteacăn [pond], 46°10ʹ53ʺN 25°57ʹ27ʺE, 738 m a.s.l., 26.vii.2011, 1 ♂ (ap) 1 ♂ (ma) 2 ♀♀ (ma). Harghita County:

Gheorgheni [swamp], 46°45ʹ02ʺN 25°41ʹ13ʺE, 919 m a.s.l., 05.v.2017, 2 ♂♂ (ap). Maramureș County: Baia Borșa [pond], 47°41ʹ00ʺN 24°47ʹ21ʺE, 881 m a.s.l., 03.v.2017, 2 ♂♂ (ma) 2 ♀♀ (ap) 1 ♀ (ma); Gutâi Mountains [stream], 47°42ʹ10ʺN 23°49ʹ53ʺE, 1127 m a.s.l., 01.v.2017, 1 ♂ (ma); Șesuri [swamp], 47°35ʹ47ʺN 24°57ʹ04ʺE, 1070 m a.s.l., 04.v.2017, 1 ♂ (ma) . Mureș County: Lăpușna [stream], 46°46ʹ06ʺN 25°13ʹ10ʺE, 859 m a.s.l., 12.vii.2014, leg. & det. P. Boda, 4 ♂♂ (ma) 1 ♂ (ap) 2 ♀♀ (ma) 1 ♀ (ap) ( PBDH) . Neamț County: Pluton [pond], 47°11ʹ14ʺN 26°01ʹ41ʺE, 740 m a.s.l., 01.viii.2011, 1 ♀ (ma). Suceava County: Gheorghițeni [stream], 47°21ʹ43ʺN 25°26ʹ52ʺE, 757 m a.s.l., 04.v.2017, 1 ♂ (ap).

Published records.? Horváth (1897),? Montandon (1907),? Benedek (1970),? Bucșa (1970), Kis & Stănescu (1994), Kecskés (1999),? Davideanu et al. (2004), Ilie (2014).

Remarks. In Romania, this species was identified at 10 sites at an elevational range of 738–1150 m a.s.l. ( Fig. 1 ). It was found from April to August in streams, lakes, bogs and ponds. The apterous/macropterous ratio was: 0.38: 0.62 (total 10/16).

The vertical distribution is not overlapping in G. asper and G. lateralis ( Fig. 1 ), both being known as vicariant species (e.g., Jeziorski et al. 2013). Some old records of G. lateralis by Horváth (1897), Montandon (1907), Benedek (1970), Bucșa (1970), and Davideanu et al. (2004) require revision since they come from lowlands and most probably refer to G. asper .

North European populations of G. lateralis are univoltine and dimorphic through the year ( Vepsäläinen 1973, 1974b), whereas in Poland it is known as bivoltine ( Wróblewski 1980).

Distribution. Palaearctic: Euro-Siberian (cf. Andersen 1995, Damgaard et al. 2014). For the Romanian distribution, see Fig. 10 .

Figures

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

FIGURE 10. Distribution of Gerris asper (Fieber, 1860) (black dots) and G. lateralis Schummel, 1832 (white squares) in Romania. Blank shapes represent published records, question marks represent dubious published records of G. lateralis and solid shapes represent records from this study.