Thaumatogelis audax (Olivier, 1792)

Verheyde, Fons, Hoekstra, Paul, Libert, Pierre-Nicolas, Meijer, Hilco, Ketelaere, Augustijn De, Vandaudenard, Thibaud, Belgers, Dick & Brosens, Edwin, 1880, Two hundred and five ichneumonid wasps reported for the first time in Belgium and the Netherlands (Hymenoptera: Ichneumonidae), Belgian Journal of Entomology 122, pp. 1-142 : 101

Thaumatogelis audax (Olivier, 1792)

Thaumatogelis spp. closely resemble Gelis spp. (see above). Both genera have an antlike habitus and wingless females. Some characteristics to distinguish them consist of a fused second and third tergite, the fusion of pro- and mesonotum and the absence of dorsolateral carinae on the first abdominal segment (more details see SCHWARZ, 1995). All species parasitise spiders’ egg sacs and some of them hibernate as adults in ground vegetation ( SCHWARZ & SHAW, 2000).

Thaumatogeli s audax has the second and third tergite entirely fused. Both these tergites have a distinct transverse black band, on the otherwise entirely orange metasoma. In contrast to T. sylvicola (Förster, 1850) these tergites are densely hairy. Furthermore, the third antennal segment is 1.8-2.0x as long as wide and the frons does not have any distinct punctures ( SCHWARZ, 2001). The head is black. T. audax appears to prefer open habitats (coastal dunes, moorlands) where it is able to search for its arachnid hosts (in casu: Agroeca spp. ; see SCHWARZ & SHAW, 2000). First report for Belgium and the Netherlands.

MATERIAL EXAMINED:

BELGIUM: • 1 ♀; Stokkel (BR); 4/vii/1932; A. Crèvecoeur leg.; coll. KBIN/RBINS (coll. Crèvecoeur); F. Verheyde det. • 1 ♀; Geel , Belsbroekbos (AN); 51°09’17”N 5°04’28”E; 21/x/2012; L. Jansen leg.; field observation; C. Thirion & J. Devalez det. (ObsID: 71790082) . • 1 ♀; Stabroek , Grenspark Kalmthoutse Heide (AN); 51°21’05”N 4°22’48”E; 25/iv/2013; R&B Foquet leg.; field observation; F. Verheyde det. (ObsID: 75458297) . • 1 ♀; Retie (AN); 51°15’45”N 5°02’59”E; 3/ix/2019; N. Van Loco leg.; field observation; F. Verheyde det. (ObsID: 179236448) • 1 ♀; Couthuin (LG); 50°31’09”N 5°07’42”E; 11/v/2020; P. Vanmeerbeeck leg.; field observation; F. Verheyde det. (ObsID: 191154624).

THE NETHERLANDS: • 1 ♀; Huijbergen , Grenspark Kalmthoutse Heide (NB); 51°25’10”N 4°22’30”E; 25/iv/2013; H. Nouwens leg.; field observation; F. Verheyde det. (ObsID: 178538351) . • 1 ♀; Geijsteren (LIN); 51°32’22”N 6°03’28”E; 21/xii/2019; T. Martens leg.; field observation; F. Verheyde det. (ObsID: 183307016) . • 1 ♀; Wellerlooi , Wellsche Heide (LIN); 51°32’45”N 6°08’51”E; 20/i/2020; T. Martens leg.; field observation; F. Verheyde det. (ObsID: 183307016) . • 1 ♀; Lemele (OR); 52°27’53”N 6°23’54”E; 11/iii/2020; H. Soepenberg leg.; field observation; F. Verheyde det. (ObsID: 186517284) . • 1 ♀; Udenhout , De Loonse en Drunense Duinen (NB); 51°38’18”N 5°07’53”E; 28/vi/2020; R. Hofland & W. Teunissen leg.; field observation; F. Verheyde det. (ObsID: 195216970) […] .