Contribution to the Knowledge of the Aquatic Beetle Genus Berosus Leach (Coleoptera: Hydrophilidae) in Serbia - page 01

Materials and Methods

The adult specimens of Berosus were collected in inundation zones of the Danube, Sava and Tisza Rivers, near irrigation canals and different stagnant waters (natural ponds, oxbows, clay, sand pits etc.), mainly in the lowlands of Northern Serbia - Vojvodina (Pannonian Plain) using aquatic invertebrate nets and UV lamps.

The species of the genus Berosus were found at 46 sampling sites in Serbia, mainly in the lower part of the country. The map of the investigated sites is shown in Fig. 2. The additional information related to the sampling sites of the species is given in Tab. 1.

 

Fig01
Figure 1: Attraction of beetles to UV light.

 

Fig02
Figure 2: Recent records of the Berosus species in Serbia (2011-2015 period), map by Google Maps.

 

Tab01

 

The beetles were killed in the field by ethyl acetate. The collected specimens were examined in the laboratory by stereomicroscope Leica S8 APO and identified using appropriate keys for identification of European water scavenger species (Hansen, 1987; Hebauer & Klausnitzer, 1998; Schödl, 1991, 1993; Csabai et al, 2002). The collected material is preserved in fully dry conditions (fixed on cardboards or packed in paper tubes) and stored in the first author's private collection.

 

Results and Discussion

During the research period a total of 535 specimens belonging to 6 species of the genus Berosus were analyzed. All specimens were collected by the first author, except where notified.

 

Berosus (Berosus) affinis Brullé, 1835

Biology: In temporary and permanent stagnant or slow moving waters; shallow pools or ponds with grassy bottom, or coastal areas of streams and rivers.

General distribution: Widely distributed in the Western Palearctic.

Literature data: Belgrade, without precise data - (DQ56), 1993, leg. Guido Nonveiller (Schödl, 1993).

Material examined: Skelice, Radenković - (CQ87), 17 Aug 2011, 1♀; Šumareva ćuprija, Zasavica I - (CQ87), 18 Aug 2011, 1♀; Valjevac, Zasavica I - (CQ87), 18 Aug 2011, 3♀, 1♂; Valjevac, Zasavica I - (CQ87), 23 Apr 2012, 1♀; Čodakut, Kanjiža - (DS20), 19 Jun 2015, 1♂, 1♀; wetland, Selevenjska Pustara - (DS11), 07 Aug 2015, 6 spec. The specimens were collected using UV lamp and by sweeping among submerged aquatic vegetation.

Remarks: According to the occurrence frequencies in field samples of water beetle, in Hungary this species is regarded as extremely rare (Csabai, 2003).

Berosus (Berosus) geminus Reiche & Saulcy, 1856

Biology: In inundation zone of large rivers and oxbows densely covered with floating and submerged vegetation.

General distribution: Stagnant freshwater habitats in Middle and Southeastern Europe, mainly in floodplains and oxbows along the Danube River (Csabai & Móra, 2003; Przewoźny & Bucszyński, 2008; Turić et al, 2008).

Material examined: Sadžak, Noćaj - (CQ87), 20 May 2011, 1♀, leg. Mihajlo Stanković; Pig Farm, Banovo polje - (CQ77), 23 Apr 2012, 2♂; Borkovačko jezero, Fruška Gora - (DQ08), 27 Apr 2012, 1♀; Šumareva ćuprija, Zasavica I - (CQ87), 27 Apr 2012, 1♀; Bakulja, Bogojevo - (CR44), 23 Jul 2012, 1♂; Tikvara, Kovilj - (DR20), 23 May 2014, 1♂, 9 spec. All specimens were collected by sweeping among submerged aquatic vegetation.

Remarks: This species is noted in the red list of endangered species of Germany (Geiser, 1998) and regarded as a highly endangered species in Bayern (Hebauer et al, 2003). According to the occurrence frequencies in field samples of water beetles, in Hungary this species is regarded as extremely rare (Csabai, 2003). The first record of this species in Croatia appears in 2005 (Turić et al, 2008). B. geminus is a new species for the fauna of Serbia (Fig. 3).

 

Berosus (Berosus) luridus (Linnaeus, 1761)

Biology: In stagnant, rather eutrophic, open, shallow pools or ponds with grassy and somewhat clayey bottom with dense submerged vegetation.

General distribution: Widely distributed throughout the Palearctic region.

Literature data: Morović, without precise data - (CQ58), 1993, leg. Zoufal (Schödl, 1993).

Material examined: Brickyard Ker, Subotica - (CS90), 28 Mar 2011, 2 spec.; Bukvać, Subotica - (CS91), 03 Jun 2011, 1 spec.; Brickyard Bačka Opeka, Subotica - (CS90), 05 Apr 2012, 7 spec.; Hrvatski Majur, Subotica - (CR99), 11 Apr 2012, 11 spec.; Šumareva Ćuprija, Zasavica I - (CQ87), 27 Apr 2012, 1 spec.; a pond next to the highway, Bačko Dobro Polje - (DR03), 24 May 2012, 5 spec.; Trebljevine, Banovo Polje - (CQ77), 20 Jun 2012, 1 spec.; Vilovo Pond, Vilovo - (DR31), 02 May 2013, 1 spec.; Small lake next to Čikera, Čantavir - (CR99), 19 May 2014, 2 spec. All specimens were collected by sweeping among submerged aquatic vegetation.

Remarks: Widely distributed across the Serbian lowlands but not so abundant. This species is enlisted as a highly endangered species in Bayern (Hebauer et al, 2003).

 

Fig03
Figure 3: Adult female of the Berosus geminus, a new species for Serbian fauna (photo by Gabor Mesaroš).