Key to genera of New World Nemoleontini with pretarsal claws that close upon the distal tarsomere

1. Antennal fossa separated from ocular rim by more than greatest width of pedicel; mid leg shorter than foreleg which is shorter than hindleg; midtibia usually swollen much broader than hind tibia; subcostal area narrowed at origin of cubital fork to less than diameter of radial vein (except Dimarella riparia) (Subtribe Dimarellina).................................. 2

— Antennal fossa separated from ocular rim by less than greatest width of pedicel; midleg as long as or longer than foreleg or foreleg longer than hindleg; midtibia not swollen broader than hindtibia (except few species of Purenleon Stange and Navasoleon tarsalis (Fig. 26); subcostal area not narrowed to less than diameter of radial vein (Subtribe Nemoleontina)......... 3

2. Tibial spurs present on all legs; posterior fork of vein CuA and CuP + 1A parallel with each other and hind margin for long distance; male ectoproct with elongate postventral lobe........................................................ Dimarella Banks

— Tibial spurs absent at least on midleg and hindleg; posterior fork of vein CuA runs obliquely to hind margin; male ectoproct without postventral lobe (Brazil)......... Brasileon Stange

3. Tibial spurs absent............................................. Navasoleon Banks — Tibial spurs present............................................................. 4

4. Tibiae with long setae, more than four times longer than diameter of tibia; foretibial spurs longer than basal three tarsomeres; hindfemur with sense hair; distal tarsomere somewhat flattened dorsoventrally with setal brush lacking along midline (Chile; coastal Peru).............................................. Sericoleon Esben-Petersen

— Tibiae with short setae, longest less than twice as long as tibial diameter; foretibial spurs shorter than basal two tarsomeres; hindfemur without sense hair; distal tarsomere not flattened and with setae on midline (Argentina)............................................... 5

5. Setal brush on distal tarsomere usually with apically hooked setae; hindleg tarsomere 2 usually over 4 × longer than wide, sometimes as long as basitarsus; female terminalia with posterior gonapophysis produced thumb-like; ectoproct without digging setae...... Elachyleon Esben-Petersen

— Setal brush on distal tarsomere without hooked setae; hindleg tarsomere 2 at most 2.5 × longer than wide; female terminalia with posterior gonapophysis produced finger-like; ectoproct with short digging setae............................................... Rovira Navás