Key to Mecophilus species

1. Cephalic plate sub-trapezoidal, with posterior part wider than anterior part (Figs 29B, 31B); denticle of tarsungulum small and positioned above base of tarsungulum (Fig. 31D)................................................. M. neotropicus

- Cephalic plate sub-rectangular (Fig. 32B); denticle of tarsungulum large and positioned close to base of tarsungulum (Fig. 32D)................................................................................ M. tupiniquim n. sp.