Identification key to the Swedish species of Enicospilus

1. Fore wing lacking sclerites in glabrous area of discosubmarginal cell (Fig. 13C); vein Rs+2 r conspicuously curved before junction with pterostigma; large species, wing length about 20 mm .................................................................................................. E. inflexus (Ratzeburg, 1844) [For separation between E. inflexus (Ratzeburg, 1844) and E. undulatus (Gravenhorst, 1829), see Broad & Shaw 2016.]

– Fore wing with at least one distinct sclerite in discosubmarginal cell (Figs 4 A–D, 13A–B); vein Rs+2 r slightly sinuate before junction with pterostigma; smaller species, wing length usually less than 16 mm ....................................................................................................................................... 2

2. Fore wing lacking any trace of central sclerite; distal sclerite very weak or absent (Fig. 13A); clypeus in lateral view flattened (Fig. 14B) ................................................. E. repentinus (Holmgren, 1860)

– Fore wing with central sclerite present, but sometimes completely translucent (Figs 4 A–D, 13B); clypeus in lateral view distinctly convex (Fig. 14A) ( E. ramidulus species group) ......................... 3

3. Fore wing with central sclerite completely translucent (Fig. 13B) ..................................................... ..................................................................................................... E. merdarius (Gravenhorst, 1829) – Fore wing with central sclerite distinctly pigmented (Fig. 4 A–D) ................................................... 4

4. Antenna with central and apical flagellomeres very slender with central and apical segments more than 2 times as long as wide (Fig. 3 G–H); number of flagellomeres 53–56; occipital carina only slightly curved before indicated junction with hypostomal carina (Fig. 6B); epicnemial carina between mesopleural angles and sternal part almost straight (Fig. 12A); central sclerite in glabrous area in fore wing usually more circular in shape, largely unpigmented; central and proximal sclerite closer to each other (Fig. 4C). Small species, fore wing length 12–13 mm ....... E. ryrholmi sp. nov.

– Antenna with central and apical flagellomeres at most 1.8 times as long as wide (Fig. 3 A–F); occipital carina distinctly curved before indicated junction with hypostomal carina, (Fig. 6A); epicnemial carina between mesopleural angles and sternal part sinuous (Fig. 12B); central sclerite in glabrous area in fore wing more semi-ovoid in shape, often elongate; central and proximal sclerites further apart (Fig. 4 A–B, D) ......................................................................................................................... 5

5. Mesosoma usually with extensive dark brown patches; central sclerite in fore wing mostly narrow, at most as long as wide (Fig. 4A); distance between central and proximal sclerites usually distinctly longer than basal side of proximal sclerite; central sclerite mostly entirely pigmented .................................................................................... E. combustus (Gravenhorst, 1829)

– Mesosoma lacking distinct dark patches, uniformly testaceous; central sclerite usually longer than wide (Fig. 4 B–C); distance between central and proximal sclerites almost equal to basal side of proximal sclerite; central sclerite mostly largely unpigmented proximally ..................................... 6

6. Antenna with central and preapical flagellomeres shorter, at most 1.5 times as long as wide (Fig. 3 A–D) ....................................................................................................................................... 7

– Antenna with central and preapical flagellomeres longer, at least 1.7 times as long as wide (Fig. 3 E–F) ........................................................................................................................................ 8

7. Antenna with 51–56 flagellomeres; temples very strongly narrowed behind eyes, head with no gap between eye and lateral ocelli (Fig. 5A); central and apical flagellomeres about 1.3 times as long as wide (Fig. 3 A–B) ..................................................................................... E. cerebrator Aubert, 1966

– Antenna with 59–62 flagellomeres; temples strongly buccate, head with distinct gap between ocelli and eye (Fig. 5B); central and apical flagellomeres about 1.5 times as long as wide (Fig. 3 C–D) ...................................................................................................... E. cederbergi sp. nov.

8. Metasoma in female abruptly black-tipped from the 5th (in females) or 6th (in males) tergite; hind tarsal claws in female conspicuously curved (Fig. 15A).................... E. ramidulus (Linnaeus, 1758)

– Metasoma never abruptly black-tipped; hind tarsal claws in female not conspicuously curved (Fig. 15B) .......................................................................................................................................... 9

9. Head in lateral view with temples narrow, at most about 0.4 times the width of compound eye (Fig. 9I); face generally with extensive yellow markings (Fig. 9 G–H); face narrow in anterior view (Fig. 9 G–H); lateral ocellus touching compound eye ................................. E. adustus (Haller, 1885)

– Head in lateral view with temples wide, about 0.7 times the width of compound eye (Fig. 9C, F); face generally more testaceous; face wider in anterior view (Fig. 9 A–B, D–E); lateral ocelli often with more or less distinct gap between lateral ocellus and compound eye .................................... 10

10. Number of flagellomeres 56–59; head in anterior view more rounded (Fig. 9 D–E); ocelli small, gap between lateral ocelli and inner margin of compound eye wide, about 0.2–0.3 times the diameter of ocellus ............................................................................................. E. myricae Broad & Shaw, 2016

– Number of flagellomeres 62–67; head in anterior view distinctly transverse (Fig. 9 A–B); ocelli large, gap between lateral ocelli and inner margin of compound eye narrow, about 0.1 times the diameter of ocellus .......................................................................................... E. intermedius sp. nov