Ichneumon nitidulus Fabricius 1793: 184. Holotype ♀; Italy (MNHN) (examined).
Cleptes nitidula: Dahlbom 1831: 25, Boheman 1851: 185, Boheman 1864: 65, Thomson 1870: 102, Sahlberg 1910: 99, Forsius 1922: 94.
Cleptes nitidulus: Zetterstedt 1840: 434, Dahlbom 1854: 14, Borries 1891: 90, Aurivillius 1911: 5, Hellén 1920: 206, Jansson 1922: 33, Pulkkinen 1926: 25, Hellén 1935: 8, Berland & Bernard 1938: 24, Benno 1950: 47, Haupt 1957: 31, Erlandsson 1971: 88, Tumšs 1976: 23, Nilsson 1986: 86, Vikberg 1986b: 67, Rassi et al. 1992: 135, Móczár 1997: 40, Berglind 2003: 13, Söderman & Vikberg 2003: 44, Soon 2004: 44, Karlsson 2008, Franzén & Norén 2009: 40, Fritz & Larsson 2010: 151, Orlovskytė et al. 2010: 153, Paukkunen 2010: 538, Allearter.dk 2010, Rosa & Soon 2012 Dyntaxa 2013.
Material examined. * Estonia: Kärgula, malaise trap, 21.VI–3.VII.2007, 2 ♀♀ (M. Soon); Nurmetu, 20.VII.2004, 1 ♂ (V. Soon); Tartu, yellow pan trap, 27.VII.2009, 1 ♀ (V. Soon); Tartu, pitfall trap, 25.VI–22.VII.2010, 5 ♀♀ and 2 ♂♂ (M. Kruus); Tartu, pitfall trap, 30.VI–27.VII.2011, 2 ♀♀ and 1 ♂ (M. Kruus).
Distribution. Denmark, * Estonia, Finland, Latvia, Sweden, Russian Fennoscandia.—Westpalearctic: from West Europe to Asia Minor (Linsenmaier 1959).
Remarks. The species is recorded from all countries except Lithuania and Norway. Most records are from Denmark and southern Sweden. In Finland, the species has been found in only two localities (Sa: Taipalsaari and Kl: Parikkala) and it has been classified as regionally extinct (Paukkunen 2010). In Russian Fennoscandia, two specimens have been collected from the Karelian Isthmus (Ik: Metsäpirtti [=Zaporozhskoe] and Rautu [= Sosnovo]) (Forsius 1922, Pulkkinen 1926).