Gasteruption tournieri Schletterer, 1885

Figs. 217–225.

For synonymy see van Achterberg & Talebi (2014).

Diagnosis: The body length of females is 11–17 mm, ovipositor is 12–18 mm long. Body length of males is 9–14 mm. Species with a long ovipositor 4.5–7.9× as long as third tibia. The ovipositor sheath with whitish apex 1.7–3.0× as long as third basitarsus. Head shiny, narrowing behind the compound eyes, with wide and semitransparent occipital carina with a small depression in the middle. Antesternal carina small, third basitarsus with whitish marking. Mesonotum usually shiny, with transverse rugose pattern.

Distribution: (Fig. 225): Palaearctic species known from most of Europe and Middle East, recorded from the following countries: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, France + Corsica, Greece, Germany, Hungary, Italy + Sardinia and Sicily, Macedonia, Moldova, Montenegro, Netherlands, Poland, Romania, Serbia, Slovakia, Slovenia, Spain, Switzerland, Turkey and Ukraine, doubtfully in the United Kingdom (Ferrière 1946; Šedivý 1958; Oehlke 1984; Madl 1989; Pagliano & Scaramozzino 2000; Wiśniowski 2004, 2020; van Achterberg 2013; Strumia & Pagliano 2014; van Achterberg & Talebi 2014; Ceccolini 2016; Vas 2016; Madl & Mitroiu 2019, and personal records). In Asia from Iran, Israel, Jordan, Syria, Tajikistan and Turkey (van Achterberg & Talebi 2014, Özbek 2020, and personal records).

Šedivý (1958; 1989) recorded this species both from the Czech Republic (Bohemia and Moravia) and from Slovakia. A common and widespread species recorded most from warmer regions but rarely occurring in higher altitudes. In the Czech Republic it is known from 71 localities, while recorded from 43 until 1990 and 55 localities after 1990. In Slovakia only seven localities until 1990 but 14 after 1990, with very numerous records especially from warmer parts in the south of the country (Tab. 2).

Biology: Recorded from June to September. Hosts are unknown, supposed to be species of the genus Hylaeus (Wall 1994; Jakubzik & Cölln 1997) or smaller species of Megachilidae of the following genera: Chelostoma, Heriades and Osmia (Wall 1994). Recorded in galls of Andricus kollari, where species of Hylaeus confusus complex are supposed to be hosts of this species (P. Bogusch, unpublished data). Adults visit flowers of the families Apiaceae and Asteraceae, also Paliurus spina-christi (Rhamnaceae) (Wall 1994).

Conservation: Widespread species, which is very numerous especially in the warmer regions of both countries. The number of records and localities is greater after the year 1990. Red List Category: LC—least concern (Tab. 2).