Bathythrix claviger (Taschenberg, 1865)

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 : 88

Bathythrix claviger (Taschenberg, 1865)

Species from the genus Bathythrix are not that hard to recognise within Phygadeuontinae by their habitus. They are all slender (or very slender), their notaulus is long, their propodeum has a specific carination and their first tergite often has longitudinal carinae ( TOWNES, 1970a). Several species are hairy and/or have tentorial pits.

Bathythrix claviger is a distinctive species within the genus. Its ovipositor is very long (1.9– 2.7× the hind tibia) and downcurved. It is mainly black, but it has silvery hairs on its mesopleura and frons. Its legs are reddish brown, but the hind tibiae and the tarsi are blackish. It is a known parasitoid of sawflies, namely Diprion (Symphyta: Diprionidae ) and Strongylogaster spp. (Symphyta: Tenthredinidae ) ( SAWONIEWICZ, 1980).

First report for Belgium; confirmed in the Netherlands.

MATERIAL EXAMINED:

BELGIUM: • 1 ♀; Hoboken , Hobokense Polder (AN); 51°11’21”N 4°20’47”E; 12/vi/2010; L. Janssen leg.; field observation; G. Broad & F. Verheyde det. (ObsID: 48568025) . • 1 ♀; Gent , Bourgoyen (OVL); 51°03’28”N 3°40’41”E; 16/v/2014; W. Decock leg.; field observation; F. Verheyde det. (ObsID: 84535872) . • 1 ♀; De Panne , Krakeelduinen (WVL); 51°05’15”N 2°34’43”E; 7/xi/2017; H. Vanhulle leg.; field observation; F. Verheyde det. (ObsID: 145818193) .

THE NETHERLANDS: • 1 ♀; Linschoten (UT); 52°03’38”N 4°55’19”E; 8/vi/2015; C. Witkamp leg.; field observation; G. Broad det. (ObsID: 103506800) . • 1 ♀; Strijensas (ZH); 51°42’15”N 4°32’28”E; 14/v/2020; A. Den Tuinder leg.; field observation; F. Verheyde det. (ObsID: 191334763) .