Gasteruption nigrescens Schletterer, 1885

Bogusch, Petr, 2021, The genus Gasteruption Latreille, 1796 (Hymenoptera: Gasteruptiidae) in the Czech Republic and Slovakia: distribution, checklist, ecology, and conservation status, Zootaxa 4935 (1), pp. 1-63 : 40-41

Gasteruption nigrescens Schletterer, 1885

Figs. 158–166 .

For synonymy see van Achterberg & Talebi (2014).

Diagnosis: A larger species with body length of both sexes between 9–14 mm, ovipositor length is 8–13 mm. Species with a long ovipositor, the ovipositor sheath 3.9–5.2× as long as third tibia, with only a short part of the apex lightened (0.1–0.9× as long as third basitarsus). Head elongated behind the compound eyes, with a narrow but welldeveloped occipital carina, matte and finely sculptured. Mesonotum matte and coarsely rugose, mesopleuron finely rugose with a coarser sculpture posteriorly (near the coxae of the second and third pair of legs).

Distribution: ( Fig. 166 ): Palaearctic species occurring in central and south-east Europe and in Asia. Recorded in the following countries of Europe: Austria, Croatia, Czech Republic, Germany, Greece, Hungary, Italy, Montenegro, Poland, Russia, Serbia, Slovakia, Spain, Switzerland, Turkey and Ukraine ( Ferrière 1946; Šedivý 1958; Madl 1990; Pagliano & Scaramozzino 2000; Schmid-Egger & Saure 2010; Bogusch et al. 2018; Madl & Mitroiu 2019; Wiśniowski 2020, and personal records). Recorded in Asia from Iran, Jordan, Kazakhstan, Mongolia and Turkey ( van Achterberg & Talebi 2014, Özbek 2020, and personal records).

Šedivý (1958; 1989) recorded this species only from Slovakia, Bogusch et al. (2018) brought the first records for the Czech Republic ( Bohemia). It is recorded both from the Czech Republic and Slovakia with more records in recent times, probably due to the result of comprehensive studies on reed galls (see Bogusch et al. 2018). In the Czech Republic, it was recorded in four localities in Bohemia after 1990, and these records are the first for this region. In Moravia, it was first recorded in 1941 (Brumovice), with four additional recent records from warmer parts of the region. In Slovakia, it is known from 15 localities, while it is numerous in the warmest parts of the country around Štúrovo ( Tab. 2). A new species for Moravia.

Biology: Recorded from June to August. Recorded from the nests of smaller bees of the family Megachilidae , with Hoplitis leucomelana (Kirby) being the only host reported in literature ( Malyshev 1964; Bogusch et al. 2018) until Bogusch et al. (2018) confirmed this species invading nests of a related bee species Heriades rubicola Perez. The records on Pemphredon fabricii as hosts are probably erroneous ( Bogusch et al. 2016, 2018). Visited plants have not been reported but we have collected this species on Apiaceae .

Conservation: Rare species of xerothermic habitats in the warmest parts of both countries, more numerous in Slovakia. It frequently occurs also on reed beds, and also in mesic regions (Jestřebí env. in Bohemia, where it is relatively common in reed galls). In recent years there are more findings although it is still rare and needs further focus. What is interesting is, why it occurs in wetlands and xerothermes—the explanation could be in the fact that most of the xerothermes in the Czech Republic and Slovakia have been destroyed or changed into fields or forests, and hymenopterans search for nesting and food resources on wetlands (see Heneberg et al. 2018). Red List Category: VU—vulnerable ( Tab. 2).

Figures

FIGURE 166. Distribution map of Gasteruption nigrescens in the Czech Republic and Slovakia. Full circles represent distribution after 1990 and empty circles distribution until 1990.

FIGURES 158–165. Gasteruption nigrescens Schletterer, 1885. 158—female, lateral habitus, 159—male, lateral habitus, 160—female, lateral head, 161—female, frontal head, 162—female, dorsal head, 163—female, lateral mesosoma, 164—female, dorsal mesosoma, 165—female, third leg. Scale bars represent 1 mm.