Key to the species of Eugubinus (modified after Wygodzinsky, 1966)
1 Body length more than 20 mm; apterous; basal fourth of fore femur devoid of spines (Fig. 28).............. E. canalanus
- Body length 17 mm or less; winged; spines of fore femur beginning almost at base of segment....................... 2
2 Body length 17 mm; fore femur dark, with one broad, subapical, white annulus removed from apex by its own length; pronotum dorsally with a pair of anteriorly converging whitish bands............................................. E. leleupi
- Body length less than 17 mm; colour not as above........................................................... 3
3 Body length 16 mm; colour piceous; fore coxae reddish; abdomen strongly enlarged apically............. E. strangulatus
- Body length less than 16 mm; body colour and shape of abdomen not as above.................................... 4
4 Head piceous with a posterior pale yellowish median line and a wide pale fascia laterally between eyes and base of antennae; fore femora dark, dorsally with two submedian whitish spots; third segment of rostrum whitish (Figs. 29–31)...................................................................................................... E. annulatus
- Colour not as above................................................................................... 5
5 Anterior and posterior lobe of pronotum equal or subequal in length............................................ 6
- Anterior lobe of pronotum distinctly shorter than posterior lobe................................................ 8
6 Head and pronotum fuscous with central pale longitudinal lines; apices of posterior femora black (Fig. 25: adult syntype; Fig. 26: nymph)................................................................................. E. reticolus
- Head and pronotum uniformly piceous; apices of posterior femora whitish....................................... 7
7 Posterior femora with entire apical region greyish white (Fig. 24)..................................... E. intrudans
- Posterior femora with large subapical white annulus, extreme apex black (Fig. 32: holotype, mid and hind legs mutilated).............................................................................................. E. forsteri
8 Visible first and second segment of labium strongly incrassate and strongly bent between first and second segment (Fig. 6); eyes large, touching ventral margin of head in lateral view (Fig. 5).......................................... E. araneus
- Visible first and second segment of labium very slightly incrassate and not strongly bent; eyes not touching ventral margin of head in lateral view (Fig. 27).................................................................. E. papuensis