Type species: Hesperia librita Plötz, 1886, by original designation.

Librita is another genus that possesses traits suggesting potential affinity with Onespa and Buzyges as noted above. The genus was erected by Evans (1955) to embrace three species of hesperiines from the northern neotropics that he characterized by a relatively short antennal club and a “broad, conspicuous stigma”, among other traits. One species, Librita raspa Evans, 1955, has subsequently been transferred to Paratrytone as the senior synonym of Paratrytone miahua Steinhauser, 1996 (Mielke and Casagrande 2002). The remaining two species attributed to Librita (Mielke 2005a) have not been critically examined, except by Godman and Salvin (1879 -1901) and Evans (1955).

Description. Palpi quadrate, shaggy, 3rd segment robust, nearly erect, barely exceeding scales of second segment. Antennae about 1/2 costa (53% on males, 50% on females); club stout, about 1/3 shaft (35% on males, 34% on females), bent to constricted apiculus beyond thickest part; nudum varies from 12 to 13 segments, subequally divided between club and apiculus (5-6 segments on club); shaft black above, yellow-orange and checked narrowly with black (broadest distad) on venter; nudum red-brown.

Wings weakly produced; forewing apex 1.3 times length along vein 2A; hindwing shorter at vein Sc+R 1 than at 2A and CuA 1; 3A about length of Sc+R 1. Male with conspicuous, broad, and continuous stigma in CuA 1 -CuA 2 and CuA 2 -2A with androconial scales extending across vein CuA 2 (Fig. 61). Hindwing origin Rs nearer to cell end than base. Forewing origin CuA 2 nearer to origin of CuA 1 than to base of wing. Sexual dimorphism minor. Wings broadly orange marked with black.

Meso- and metatibiae not spined, long fringes of setiform scales on meso- and metafemur and on metatibia, mesotibiae with one pair spurs, outer about 2/3 length of inner, metatibiae with two pairs, outer about 1/2 length of inner.

Male genitalia with gnathos bifid, arms slender and connivent, uncus narrow, bluntly bilobed at end, narrower than gnathos in dorsal view, about length of gnathos; separation of gnathos and uncus in lateral view moderately deep. Tegumen flaring cephalad, ventral arm with dorsal arm of saccus combining into a structure curved below its middle, anterior arm of saccus moderately long, narrowing to a bluntly pointed cephalic end in ventral view. Valvae simple and unarticulated, with costa/ampulla relatively straight and undifferentiated between themselves and harpe, ampulla with small dorsal triangular process caudad, harpe with dorso-caudal triangular process. Aedeagus relatively narrow and short (1.1 times length of valva), triangular processes (titillators) on right side and venter near caudal end, with cornuti consisting of two heavily sclerotized structures.

Female genitalia characterized by a short (1.6 mm), sclerotized, and slightly constricted centrally ductus bursae, straight, and shorter than corpus bursae. Lamella antevaginalis about as broad as lamella postvaginalis and excavated caudad; lamella postvaginalis also very broad with shallow caudal indentation; ostium bursae broad and shallow, twice as broad as deep. Corpus bursae weakly wrinkled longitudinally, no signa.

Distribution and richness. Librita, as here revised including only Librita librita, occurs from northwestern Mexico, through central and southern Mexico to Guatemala, and putatively Panama (Plötz 1886, Godman and Salvin 1879 -1901, Evans 1955, this study).

Discussion of the genus is included below under its single known species.