| Species | Host records for Orchestes alni | Orchestes species |
|---|
| Braconidae |
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| Agathis orchestidis (Rondani, 1877) | − | O. quercus (Rondani 1876) |
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| Apanteles weitenweberi (Amerling, | − | O. quercus (Amerling 1862) |
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| 1862) | | |
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| Apanteles breviventris (Ratzeburg, 1848) | − | O. quercus (Ratzeburg 1848; Rondani |
|---|
| | 1872) |
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| Centistes delusorius (Förster, 1863) | − | O. testaceus (Viramo 1968) |
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| * Colastes braconius Haliday, 1833 | − | O. fagi (Marshall 1890; Beirne 1946; |
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| | Crèvecoeur 1950; Woodcock and |
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| | Vanbergen 2008); O. hortorum |
|---|
| | (Shaw and Askew 1976) |
|---|
| * Doryctes striatellus (Nees, 1834) | − | O. fagi, O. pilosus, O. quercus, |
|---|
| | O. testaceus (Tobias et al. 1986) |
|---|
| Eubazus semirugosus (Nees, 1816) | − | O. quercus (Rondani 1877) |
|---|
| * Eubazus minutus (Ratzeburg, 1848) | Fahringer 1922, Tobias 1971; | O. fagi (Ratzeburg 1848; Rondani |
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| current study | 1872; Rudow 1918; Tsankov and |
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| | Stalev 1992); O. quercus (Tobias |
|---|
| | et al. 1986) |
|---|
| Leiophron fulvipes (Curtis, 1833) | − | O. calceatus (Rondani 1872) |
|---|
| Perilitus fagi Haeselbarth, 2008 | − | O. fagi (Haeselbarth 2008) |
|---|
| * Spathius brevicaudis Ratzeburg, 1844 | − | O. fagi, O. pilosus, O. quercus, |
|---|
| | O. testaceus (Tobias et al. 1986) |
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| Spathius exarator (Linnaeus, 1758) | − | O. quercus (Rondani, 1872; Kudela |
|---|
| | 1974; Tobias et al. 1986) |
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| Spathius rubidus (Rossi, 1794) | − | O. quercus (Tobias et al. 1986; |
|---|
| | Abdinbekova et al. 2010) |
|---|
| * Triaspis caudata (Nees, 1816) | Fulmek (1962) | O. fagi (Rondani 1876; Wiąckowski |
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| | 1957; Kudela 1974); O. quercus |
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| | (Ratzeburg 1848; Rondani 1872; |
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| | Kudela 1974) |
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| Triaspis lugubris Snoflák, 1953 | − | O. sanguinipes (Ku et al. 2001) |
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| * Triaspis pallipes (Nees, 1816) | Oldham (1928); Tobias (1971); | O. calceatus (Kudela 1974); O. fagi |
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| current study | (Beirne 1946; Crèvecoeur 1950; |
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| | Kudela 1974; Tsankov and Stalev |
|---|
| | 1992) |
|---|
| Triaspis virginiensis (Ashmead, 1889) | − | O. pallicornis (Marsh 1979) |
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| Ichneumonidae |
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| Endromopoda detrita (Holmgren, 1860) | − | O. fagi (Eidmann 1943; Eidmann |
|---|
| | 1965) |
|---|
| Gregopimpla inquisitor (Scopoli, 1763) | − | O. testaceus (Kudela 1974) |
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| Ischnus striatus (Brullée, 1846) | − | O. quercus (Kudela 1974) |
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| Itoplectis alternans (Gravenhorst, 1829) | − | O. fagi (Rudow 1917), O. quercus |
|---|
| | (Ratzeburg 1848; Rondani 1872; |
|---|
| | Meyer 1934) |
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| Itoplectis cf. maculator (Fabricius, 1775) | Current study | – |
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| Polysphincta latistriata Ratzeburg, 1844 | − | O. quercus (Ratzeburg 1844; |
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| | Ratzeburg 1848; Rondani 1872; |
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| | Kudela 1974) |
|---|
| Scambus buolianae (Hartig, 1838) | − | O. testaceus (Pisică and Petcu 1967) |
|---|
| Scambus calobatus (Gravenhorst, 1829) | Fahringer (1922) | − |
|---|
| Scambus sagax (Hartig, 1838) | − | O. fagi (Eidmann 1943) |
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