Key to Palaearctic Xiphydriidae with simple tarsal claws on all legs

1. Vertex very smooth and almost impunctate (fig. 1A, C, F in Shinohara, 2019a); female antenna largely whitish and abdomen with lateral white spots (fig. 1A, B, D, F in Shinohara, 2019a); male with tufts of long golden hairs on abdominal sterna (fig. 1C in Shinohara, 2019a)... Monoxiphia ............................................................. M. harai

– Vertex largely covered with coarse surface microsculpture, or rather smooth but partly coriaceous with sparce large punctures (Fig. 3); female with antenna and abdomen black (Figs 1 A–F, 2); male without tufts of long golden hairs on abdominal sterna. … Konowia …....................................................................................... 2

2. Female...........................................................................................… 3

– Male. …............................................................................................ 6

3. Antenna thick, with flagellomere 2 about 1.5–1.9× longer than broad (Fig. 4 A–J, R–U); forewing with crossvein 2r-m basal to crossvein 2m-cu on vein M and vein 1A narrowly separated from or shortly fused with 2A+3A (Figs 1A, B, F, 6A, C); hind tarsomere 1 long, about 1.1–1.3× length of tarsomeres 2–4 combined (Fig. 6D); valvula 3 (apical sheath) long, about 1.0–1.1× length of valvifer 2 (basal sheath) (Figs 7, 8E, F)............................................................ 4

– Antenna thin, with flagellomere 2 about 2.7–4.4× longer than broad (Fig. 4 K–Q); forewing with crossvein 2r-m usually interstitial with crossvein 2m-cu and vein 1A fused with 2A+3A for a long distance (Figs 1 C–E, 6B); hind tarsomere 1 short, about 1.0× length of tarsomeres 2–4 combined (Fig. 6E); valvula 3 short, about 0.8–1.0× length of valvifer 2 (Fig. 8 A–D)....... 5

4. Mesoscutellum with distinct microsculpture, mat all over (Fig. 5A, D); length 9.0–12.0 mm; antenna with 12 or 13 antennomeres....................................................................................... K. betulae

– Mesoscutellum with posterior and lateral parts smooth, shiny, with few punctures (Fig. 5C, F); length 10.5–12.5 mm; antenna with 12 to 15 antennomeres................................................................... K. yasumatsui

5. Vertex fairly smooth, only sparsely punctate (Fig. 3H, K); flagellomere 2 about 3.2–4.4× longer than broad (Fig. 4Q)............................................................................................. K. megapolitana

– Vertex covered with distinct coarse surface microsculpture, except for narrow smooth areas in posterior part (Fig. 3C, F, G, J); flagellomere 2 about 2.7–3.1× longer than broad (Fig. 4N)............................................. K. kojimai

6. Mesoscutellum with posterior and lateral parts smooth, shiny, with sparse punctures (as in Fig. 5C, F); hind tarsomere 1 about 1.2–1.4× length of tarsomeres 2–4 combined; length 8.0– 11.5 mm ..................................... K. yasumatsui

– Mesoscutellum entirely covered with distinct surface microsculpture, mat (as in Fig. 5A, B, D, E); hind tarsomere 1 about 1.1–1.2× length of tarsomeres 2–4 combined; length 5.0– 10.5 mm .............................................. 7

7. Forewing with crossvein 2r-m usually situated basally to crossvein 2m-cu on vein M (as in Fig. 6A); mid and hind tibiae mostly pale brown (Fig. 6D); hind tarsomere 1 about 1.2× length of tarsomeres 2–4 combined...................... K. betulae

– Forewing with crossvein 2r-m interstitial with crossvein 2m-cu on vein M (as in Fig. 6B); mid and hind tibiae blackish brown, with only narrow apex pale brown (Fig. 6E); hind tarsomere 1 about 1.1× length of tarsomeres 2–4 combined.... K. kojimai