Ichneumonidae Latreille, 1802
Mesoleius abbreviatus Brischke, 1871
Mesoleius abdominalis Brischke, 1871
Mesoleius abietinus Teunissen, 1945
Mesoleius aceris Kasparyan & Shaw, 2003
Mesoleius admirabilis Kasparyan, 2000
Mesoleius aequabilis Holmgren, 1876
Mesoleius affinis Brischke, 1892
Mesoleius agilis Brischke, 1871
Mesoleius aglaia Teunissen, 1953
Mesoleius albopictus Brischke, 1892
Mesoleius albotibialis Strobl, 1903
Mesoleius alekhinoi Kasparyan, 2000
Mesoleius altalpinus Bauer, 1985
Mesoleius altissimus Bauer, 1985
Mesoleius analis Brischke, 1878
Mesoleius annulatus Brischke, 1871
Mesoleius ardonator Kasparyan, 2000
Mesoleius arduus Kasparyan, 2000
Mesoleius armillatorius (Gravenhorst, 1807)
Mesoleius articularis Davis, 1897
Mesoleius assiduus Holmgren, 1876
Mesoleius ater Kasparyan, 2001
Mesoleius atratus Kasparyan, 2000
Mesoleius audax Davis, 1897
Mesoleius aulicus (Gravenhorst, 1829)
Mesoleius autumnalis Woldstedt, 1874
Mesoleius axillaris (Stephens, 1835)
Mesoleius balearicus (Kriechbaumer, 1894)
Mesoleius bipunctatus Brischke, 1871
Mesoleius bisignatus Costa, 1888
Mesoleius brachyacanthus Parfitt, 1881
Mesoleius breviformis Teunissen, 1945
Mesoleius brevipalpis Thomson, 1894
Mesoleius brevis Brischke, 1871
Mesoleius caninae Bridgman, 1886
Mesoleius castaneus Habermehl, 1925
Mesoleius chicoutimiensis Provancher, 1888
Mesoleius cingulatus Brischke, 1871
Mesoleius clypearis Brischke, 1878
Mesoleius clypeator Kasparyan, 2000
Mesoleius cognatus Brischke, 1871
Mesoleius comeaui Townes, 1945
Mesoleius conformus Davis, 1897
Mesoleius congruens Holmgren, 1858
Mesoleius contractus Holmgren, 1857
Mesoleius coriaceus Holmgren, 1857
Mesoleius cressoni (Davis, 1897)
Mesoleius dubitator Kasparyan, 2000
Mesoleius dubius Holmgren, 1857
Mesoleius dudinka Kasparyan, 2001
Mesoleius dumeticola Teunissen, 1945
Mesoleius efferus Holmgren, 1876
Mesoleius elegans Parfitt, 1882
Mesoleius ephippium Tschek, 1869
Mesoleius euphrosyne Teunissen, 1953
Mesoleius excavatus (Provancher, 1875)
Mesoleius exsculptus Brischke, 1871
Mesoleius facialis Brischke, 1878
Mesoleius faciator Kasparyan, 2001
Mesoleius filicornis Holmgren, 1876
Mesoleius flavipes Brischke, 1871
Mesoleius flavoguttatus (Gravenhorst, 1829)
Mesoleius frenalis Thomson, 1894
Mesoleius frigidor Kasparyan, 2001
Mesoleius frigidus Holmgren, 1857
Mesoleius frontatus Thomson, 1894
Mesoleius fulvator Kasparyan, 2000
Mesoleius furax Holmgren, 1857
Mesoleius fuscipes Holmgren, 1857
Mesoleius fuscotrochanteratus Strobl, 1903
Mesoleius gelidor Kasparyan, 2000
Mesoleius geniculatus Holmgren, 1857
Mesoleius granulosus Kasparyan, 2000
Mesoleius groenlandicus Roman, 1930
Mesoleius grossulariae (Ratzeburg, 1852)
Mesoleius hamulator Kasparyan, 2000
Mesoleius hirtus Rudow, 1882
Mesoleius hypoleucus Teunissen, 1945
Mesoleius implicator Kasparyan, 2000
Mesoleius incisus Thomson, 1894
Mesoleius infuscator Kasparyan, 2000
Mesoleius insidiosus (Cresson, 1868)
Mesoleius insularis Roman, 1924
Mesoleius integrator (Müller, 1776)
Mesoleius intermedius (Gravenhorst, 1829)
Mesoleius irkutensis Kasparyan, 2000
Mesoleius juvenilis Holmgren, 1857
Mesoleius khasura Kasparyan, 2000
Mesoleius kiruna Kasparyan, 2000
Mesoleius kola Kasparyan, 2000
Mesoleius lapponator Kasparyan, 2000
Mesoleius laricis Teunissen, 1953
Mesoleius latipes Brischke, 1871
Mesoleius lautaretor Kasparyan, 2000
Mesoleius leucomelas Habermehl, 1903
Mesoleius lindemansi Teunissen, 1953
Mesoleius londoko Kasparyan, 2000
Mesoleius lunaris Brischke, 1871
Mesoleius maculator Kasparyan, 2001
Mesoleius maculatus Brischke, 1871
Mesoleius mediosanguineus Heinrich, 1950
Mesoleius melanius Roman, 1909
Mesoleius melanoleucus (Gravenhorst, 1829)
Mesoleius melanurus Constantineanu, 1973
Mesoleius mica Kasparyan, 2001
Mesoleius minor (Ashmead, 1902)
Mesoleius mixticolor Heinrich, 1953
Mesoleius mollator Kasparyan, 2000
Mesoleius montegratus Bauer, 1985
Mesoleius nigrans Kasparyan, 2001
Mesoleius nigromica Kasparyan, 2001
Mesoleius nigropalpis Brischke, 1871
Mesoleius nimis Heinrich, 1950
Mesoleius nivalis Holmgren, 1857
Mesoleius notator Kasparyan, 2001
Mesoleius obliquus Thomson, 1894
Mesoleius obtusator Kasparyan, 2001
Mesoleius omolon Kasparyan, 2001
Mesoleius opticus (Gravenhorst, 1829)
Mesoleius palmeni Woldstedt, 1874
Mesoleius parvus Holmgren, 1857
Mesoleius perbellus Teunissen, 1945
Mesoleius peronatus (Marshall, 1876)
Mesoleius pertaesor Kasparyan, 2001
Mesoleius pertinax Davis, 1897
Mesoleius phyllotomae Cushman, 1933
Mesoleius picticoxa Thomson, 1894
Mesoleius pictus Brischke, 1871
Mesoleius placidus Holmgren, 1857
Mesoleius pulchranotus Davis, 1897
Mesoleius pusio Holmgren, 1857
Mesoleius pyriformis (Ratzeburg, 1852)
Mesoleius robustus (Provancher, 1883)
Mesoleius roepkei Teunissen, 1945
Mesoleius ruficollis Holmgren, 1857
Mesoleius rufopectus (Provancher, 1888)
Mesoleius rugipleuris Heinrich, 1952
Mesoleius saami Kasparyan, 2001
Mesoleius scutellaris Rudow, 1886
Mesoleius seida Kasparyan, 2000
Mesoleius semipunctus Teunissen, 1945
Mesoleius smitsvanburgsti Teunissen, 1945
Mesoleius sobicola Kasparyan, 2001
Mesoleius spoliatus Teunissen, 1945
Mesoleius stejnegeri Ashmead, 1899
Mesoleius stenostigma Thomson, 1894
Mesoleius strobli Habermehl, 1925
Mesoleius styriacus Heinrich, 1953
Mesoleius subcoriaceus Strobl, 1903
Mesoleius submarginatus (Cresson, 1864)
Mesoleius subroseus Thomson, 1888
Mesoleius tarsalis (Cresson, 1868)
Mesoleius tasarensis Kasparyan, 2001
Mesoleius tegulator Kasparyan, 2001
Mesoleius tenthredinis Morley, 1912
Mesoleius terpeji Kasparyan, 2001
Mesoleius thalia Teunissen, 1953
Mesoleius thuringiacus Habermehl, 1925
Mesoleius tibialis Holmgren, 1857
Mesoleius tibiator Kasparyan, 2000
Mesoleius tinctor Kasparyan, 2001
Mesoleius titarensis Kasparyan, 2001
Mesoleius tixi Kasparyan, 2001
Mesoleius tolmachevi Kasparyan, 2001
Mesoleius tornei Kasparyan, 2001
Mesoleius torpescor Kasparyan, 2001
Mesoleius tricoloripes Costa, 1886
Mesoleius trochanteratus Brischke, 1871
Mesoleius urbanus Teunissen, 1945
Mesoleius ussuriensis Kasparyan, 2000
Mesoleius varicoxa Thomson, 1894