Key to European males of Pseudexechia

1 Terminalia large, stout (Fig. 6 A); dorsal branch of the gonostylus with a characteristically smooth whitish apex; ventral branch forming a thin plate shaped more or less like a spatula (Fig. 6 B); hypandrial lobe heavily sclerotized, bud-like by elaborate folding, triangular to subrectangular (Fig 6 A).......................................................................... 2

- Terminalia more slender (Fig. 14 A), with elongated dorsal and ventral branches of the gonostylus (Fig. 14 B); hypandrial lobe narrow rectangular, forming parallel branches medially (Fig. 14 A) ................................. trivittata group 8

2 Median ocellus small, but distinctly present (Fig. 4 A); vein R4+5 distinctly downcurved (C> D in Fig. 3A); hypandrial lobe stout, subrectangular (Fig. 6 A) ........................................................................................ trisignata group 3

- Median ocellus absent or at most tiny and vestigial; vein R4+5 almost straight (C ≤ D in Fig. 3B&D); hypandrial lobe

conic, triangular (Fig. 9 A) or enlarged and diverging apically (Fig. 11 D) ...................................... canalicula group 5 3 A dull brown species with a distinct greyish dusting (Fig. 2 A); hypandrial lobe with rounded corners (Fig. 6 A); ventral branch of gonostylus with angular basodorsal corner making the spatula broadest basally (Fig. 6 B); smooth whitish tip of dorsal branch of gonostylus evenly thick (Fig. 6 B)............... Pseudexechia trisignata (Edwards, 1913)

- Moderately to distinctly bi-coloured species without greyish dusting; hypandrial lobe sharply pointed apically (Fig. 7 A); ventral branch of gonostylus without angular basodorsal corner; smooth whitish tip of dorsal branch of gonostylus slightly dilated or constricted ............................................................................................................................... 4

4 Broad pale band along whole margin mesonotum; ventral branch of gonostylus forming small, symmetric and round spatula (Fig. 7 B); smooth whitish tip of dorsal branch of gonostylus slightly constricted (Fig. 7 B) ............................ .......................................................................................................... Pseudexechia pectinacea (Ostroverkhova, 1979)

- Without or at most narrow pale band along margin of mesonotum; ventral branch of gonostylus forming large, asymmetric spatula that is broadest apically (Fig. 8 B); smooth whitish tip of dorsal branch of gonostylus slightly dilated (Fig. 8 B) ......................................................................................................... Pseudexechia tuomikoskii sp. n.

5 Larger species, distinctly bi-coloured in dark greyish brown and yellow, with sharply defined mesonotal stripes (Fig. 2 B) ............................................................................................................................................................................... 6

- Smaller species, weakly bi-coloured to dull brown, with indistinct or fused mesonotal stripes ................................. 7

6 Gonostylus large, exposed (Fig. 9 A); dorsal branch distinctly dilated apically (Fig. 9 B); ventral branch forming large, slightly asymmetrical spatula (Fig. 9 B) ......................................... Pseudexechia canalicula (Johannsen, 1912)

- Gonostylus small, retracted (Fig. 10 A); dorsal branch not dilated apically (Fig. 10 B); ventral branch forming narrow, angular boot-shaped spatula (Fig. 10 B) ..................................................... Pseudexechia aurivernica Chandler, 1978

7 Hypandrial lobe enlarged, diverging apically (Fig. 11 A&D); dorsal branch of gonostylus apically strongly dilated, campanulate (Fig. 11 B); dorsointernal branch small (Fig. 11 B); ventral branch narrow, angular boot-shaped (Fig. 11 B) ........................................................................................... Pseudexechia monica Kjaeandsen & Chandler, 2006

- Hypandrial lobe not enlarged, conic triangular (Fig. 12 A); dorsal branch of gonostylus apically dilated, but not campanulate (Fig. 12 B); dorsointernal branch large (Fig. 12 B); ventral branch forming medium sized spatula with acute angled apicodorsal corner (Fig. 12 B)............................................................ Pseudexechia parallela (Edwards, 1925)

8 Dorsal branch of gonostylus subrectangular, with sharply truncated, whitish tip (Fig 13 A&B); dorsointernal branch forming narrow, elongated lamellate fan (Fig. 13 B); hypoproct reduced, hyaline (Fig. 13 C) ....................................... ......................................................................................... Pseudexechia latevittata Chandler & Blasco-Zumeta, 2001

- Dorsal branch of gonostylus oblong to lanceolate, without sharply truncated, whitish tip (Fig. 14 A&B); dorsointernal branch reduced to hyaline knob basally on dorsal branch (Fig. 14 B); hypoproct sclerotized, pointed (Fig. 14 C). ...................................................................................................................................................................................... 9

9 A distinctly bi-coloured species in dark greyish brown and yellow, with sharply defined thoracic stripes and triangular pale bands on abdominal tergites; dorsal branch of gonostylus shorter and smaller than ventral branch which has medial surface covered with setae and no brush apically (Fig. 14 B) ........ Pseudexechia tristriata Stackelberg, 1969

- A dull brown species with fused, hardly discernible thoracic stripes and indistinct, narrow (if any) pale bands on abdominal tergites; dorsal branch of gonostylus longer than ventral branch which has medial surface devoid of setae but a narrow brush of strong setae apically (Fig. 15 B) ................................... Pseudexechia trivittata (Staeger, 1840)