Neposa isabelae Austin and A. Warren, 2009

Austin, George T. & Warren, Andrew D., 2009, New looks at and for Onespa, Buzyges, and Librita (Lepidoptera: Hesperiidae: Hesperiinae), with new combinations and descriptions of a new genus and six new species, Insecta Mundi 2009 (89), pp. 1-55 : 46-48

Neposa isabelae Austin and A. Warren , new species

( Fig. 53-56 , 74 , 86 )

Description. Male ( Fig. 53-56 ) - forewing length = 12.7, 14.0 mm (n=2, from Guatemala); forewing weakly produced with pointed apex, termen slightly convex, conspicuous, broad, and dark brown bipartite stigma, oval in CuA 1 -CuA 2 along posterior edge of discal cell from proximad of origin of CuA 1, not reaching base of cell, but curving to vein CuA 2, divided by that vein from more or less oval element in CuA 2 -2A, diagonally across cell to vein 2A proximad, both elements surrounded by modified black scales, these shiny cephalad of anterior element, lower brush patch black, extending caudad onto vein 2A; hindwing convex, weakly lobate at tornus; dorsal forewing black marked with yellow-orange; moderately broad black outer margin, broadest apically and especially at tornus where occupying distal 1/3 of anal cell; orange macules as follows: quadrate subapical in R 4 -R 5 (smallest) and R 5 -M 1 (about 2-3 times as large); small in mid-M

2

-M

3

; postmedial in M

3

-CuA

1

, CuA

1

- CuA

2

, CuA

2

-2A, and anal cell; orange overscaling in

costal cell, proximal portion of Sc-R 1, distal portion of R 1 -R 2, in discal cell cephalad of stigma and basad, proximad in CuA

2

-2A; fringe pale brown, yellow-orange from mid-CuA

2

-2A to tornus.

Dorsal hindwing also black marked with yellow-orange; outer margin black, narrow cephalad and increasing in width caudad; anal margin black; costal margin black; yellow-orange submarginal macules in Rs-M 1, M 1 -M 3, M 3 -CuA 1, and CuA 1 - CuA 2, that in M 1 -M 3 partially divided by single line of brown scales; small yellow-orange macule in mid-discal cell; base of wing overscaled with yellow-orange setiform scales in discal cell, CuA 1 - CuA 2 and CuA 2 -2A; dense orange setiform scales along vein 2A nearly to termen; fringe yellow-orange, slightly yellower at tornus.

Ventral forewing largely orange, yellow-orange as subapical macules (as on dorsum), apical area, and more or less quadrate postmedial macules in M 3 -CuA 1, CuA 1 -CuA 2, and anterior CuA 2 -2A, the latter continued as poorly defined area of mixed dark brown and cream-colored scales to 2A; dark brown (nearly black) in base of discal cell, very base of M 3 -CuA 1, on either side of postmedial macules in CuA 1 -CuA 2 and CuA

2

-2A, and entire anal cell; fringe orange-brown cephalad, yellow caudad of 2A.

Ventral hindwing largely orange, appears mottled by vaguely paler yellow-orange patches (beneath submarginal macules of dorsum and elsewhere), submarginal markings accentuated distad and proximad by small darker red-brown macules; mixed dark brown and orange in posterior CuA 2 -2A, all of 2A- 3A, and proximal 1/3 of anal cell; long orange setiform scales along proximal 2/3 of vein 3A; fringe dull orange-brown cephalad, yellow-orange caudad of 2A.

Dorsal head olive-orange mixed with a few black setiform scales, red-brown above and behind and yellow-orange beneath eye; palpi quadrate with olive-orange and a few black setiform scales on dorsum becoming pale orange mixed with black scales on sides and pale yellow-orange on venter, 3rd segment black, stout, not exceeding scales of 2nd segment; antennae long (51% of costal length), black checked narrowly with yellow-orange on dorsum, pale yellow-orange, checked narrowly with black on venter, club relatively stout (30% of length of shaft), club black with some pale yellow-orange scaling especially on venter, nudum yellow-orange, distal segment brown, 11 (n=1) or 12 (n=1) segments; dorsal and ventral thorax black and covered with olive-orange setiform scales, pectus ochreous; legs brown proximad, orange distad with long pale yellow-orange setiform scales on femorae and tibiae, protibia smooth, red-brown epiphysis small, mesotibia spined, single pair of spurs, outer spur broken, metatibia spined, two pairs of spurs, outer about 2/3 length of inner; dorsal abdomen black covered with olive-orange setiform scales, caudal end yellow-orange; ventral abdomen pale yellow-orange.

Genitalia ( Fig. 74 , 86 ) - uncus very short, not hooked caudad in lateral view, entire and narrowing to weakly lobed caudal end in dorsal view; gnathos robust, shallowly separated from and shorter than uncus in lateral view, divided with arms slender, widely apart cephalad and approaching caudad in ventral view, about width of uncus caudad; tegumen thin in lateral view, centrally expanded in dorsal view, flaring cephalad, ventral arm combining with dorsal arm of saccus, this combined structure broadest and curved well ventrad of its middle; anterior arm of saccus relatively short and thin, mostly straight, shorter than length of uncus and dorsal portion of tegumen, moderately broad in ventral view, sides more or less parallel before bluntly rounded cephalic end; valva simple, no differentiation between costa and ampulla, latter produced dorsally to pointed triangular and slightly incurved process near juncture with harpe, harpe angled caudad with finely serrated caudal edge before another sharply pointed and incurved triangular process oriented caudad, sacculus narrow, ventral edge of valva prominently concave cephalad of middle; aedeagus straight and stout, expanded caudad, about 1.2 times length of valva, caudal end angled in ventral view, curved titillator on venter just cephalad of caudal end; vesica with two heavily sclerotized cornuti, these broad cephalad (when extruded), narrowing abruptly and sharply pointed and spike-like caudad.

Female – unknown.

Types. Holotype male with the following labels: white, printed and handprinted - / GUATEMALA: / Mpio. Acatenango, / Quisache , Chimalt- / enango – 1750 m. / X – 22 – 65 / E. C. Welling /; red, printed - / HOLOTYPE / Neposa isabelae / Austin & A. Warren /. Paratype male (ADW #98-15) with same data as holotype but 4 December 1965. Both holotype and paratype deposited at AMNH.

Type locality. GUATEMALA: Chimaltenango Department ; Acatenango, Quisache, 1750m, ca. 14 o 33’7”N, 90 o 56’32”W.

Etymology. This species is named in honor of Isabel Vargas-Fernández of Mexico City, Mexico. Isabel has been instrumental in documenting the butterfly diversity of Mexico for the past two decades, and has provided an enormous amount of help and friendship to the junior author in his studies on Mexican Hesperiidae over the past 15 years.

Distribution and phenology. The species is apparently known only from the holotype and paratype taken in south-central Guatemala during October and December of 1965.

Diagnosis and discussion. On the dorsum, N. isabelae and N. armandoi both somewhat resemble a darkly marked Librita librita . The venters are very different presenting a distinctly mottled aspect on Neposa . Besides its smaller size as the smallest of the known Neposa , N. isabelae has but two subapical macules on the forewing compared with three on N. armandoi . The ventral surface of N. isabelae is darker than that of N. armandoi , especially so on either side of vein 2A on the hindwing. Male genitalia of N. isabelae are different from both N. heras and N. armandoi . The gnathos is much narrower than on either of the latter two species and conspicuously shorter than the uncus. The saccus is shorter than on other species in the genus. The valva is relatively short with an angular harpe similar to N. heras (elongate with a curved harpe on N. armandoi ). In addition, the aedeagus has a small keel-like titillator on its ventral surface, a trait absent on both N. heras and N. armandoi .

Discussion of Neposa . Neposa is yet another hesperiine taxon of montane regions of the northernmost neotropics. These have phenotypes that are seen across a number of such taxa. Among the known Neposa , males have orange macules and females are marked by a number of white, in addition to orange, macules on the forewing, a pattern of sexual dimorphism seen among species of Onespa , Buzyges , and Paratrytone . The male of two species, N. armandoi and N. isabelae , somewhat resemble darkly marked Librita librita in dorsal view. The genitalia, however, although exhibiting some broad resemblances to those of other genera reviewed herein, have their own uniquely combined suite of characters. On males, these include a very short and unhooked uncus, a tegumen broadened centrally in dorsal view, a broad and often angled valva prominently serrated on its ventrocaudal edge with incurved triangular processes, a short and stout aedeagus, and cornuti that are broad cephalad and narrow abruptly to a spike-like caudal end. The straight, expanding, and twisted ductus bursae with internal sclerotization (but no lateral pouch) sets females apart from other apparently related taxa.

Study of various genera considered here and elsewhere (e.g., Burns 1992a, 1994b) indicates the necessity for careful examination of genitalia to make generic assignments, especially in the absence of one of the sexes. For Neposa , males are unknown for N. hestia and females for N. armandoi and N. isabelae . Fortunately for the purposes of their proper placement in Neposa , genitalia of those species lends confidence to the generic assigments made here. The males of N. armandoi and N. isabelae are unequivocally congeneric with the male of N. heras as is the single female of N. hestia with the female of N. heras .

Neposa appear to occur in highly localized habitats in humid montane environments, and seem to have very restricted geographic distributions. Perhaps because of this, they remain extremely rare in collections. Neposa heras appears to be endemic to the southern Sierra Madre del Sur, in Guerrero and Oaxaca, Mexico. At least in Oaxaca, it flies in close parapatry (or possible sympatry) with N. armandoi , the latter appearing endemic to the region. Neposa hestia is currently known only from the Sierra Madre Oriental in Veracruz, and N. isabelae is known only from Guatemala. Thus far, we lack records of Neposa from Chiapas, although we suspect the genus occurs there.

Until future field workers are able to secure male specimens of N. hestia and females of N. armandoi , the relationship between these two taxa will remain speculative. We have opted to name both populations since most taxa endemic to montane cloud forest habitats in Mexico show differentiation between eastern (northern in Oaxaca) and western (southern in Oaxaca) populations, at the species (e.g., de la Maza and Díaz 1978, Llorente and Escalante 1992) or subspecies-level (e.g., Miller and Miller 1979, de la Maza and Lamas 1982, Llorente 1984, 1986, Llorente and Luis 1988, 1992, Llorente et al. 1992).

Figures

Figure 37-60. Librita and Neposa (full data in text; ds = dorsal surface, vs = ventral surface; scale bar = 10mm). 37) L. librita, male (holotype of Augiades hecale), Guerrero, Mexico, ds; 38) same, vs; 39) L. librita, male, Michoacán, Mexico, 27 July 1996, ds; 40) same, vs; 41) L. librita, female, Chiapas, Mexico, 19-23 October 1971, ds; 42) same, vs; 43) L. librita, female, Michoacán, Mexico, 23 July 1997, ds; 44) same, vs; 45) N. heras, holotype male, Guerrero, Mexico, ds; 46) same, vs; 47) N. heras, male, Oaxaca, Mexico, 19 October 2008, ds; 48) same, vs; 49) N. heras, female, Guerrero, Mexico, ds; 50) same, vs; 51) N. hestia, holotype female, Veracruz, Mexico, 8 April 1990, ds; 52) same, vs; 53) N. isabelae, holotype male, Guatemala, 22 October 1965, ds; 54) same, vs; 55) N. isabelae, paratype male, Guatemala, 4 December 1965, ds; 56) same, vs; 57) N. armandoi, holotype male, Oaxaca, Mexico, 23 September 2007, ds; 58) same, vs; 59) N. armandoi, paratype male, Oaxaca, Mexico, 25 October 2008, ds; 60) same, vs.

Figure 71-74. Male genitalia of Librita and Neposa (full data in text; shown are lateral view of uncus, gnathos, tegumen, and saccus; dorsal view of uncus and tegumen; ventral view of gnathos uncus; internal view of right valva; ventral view of saccus; ventral, dorsal, right lateral and/or left lateral views of aedeagus; scale bar = 1 mm). 71) L. librita, Chiapas, Mexico (SRS #3425); 72) N. armandoi, Oaxaca, Mexico, holotype (GTA #14143); 73) N. heras, Guerrero, Mexico (ADW #97-112); 74) N. isabelae, Guatemala, paratype (ADW #98-15).

Figure 75-86. Rigid cornuti of Onespa, Buzyges, Librita, and Neposa (full data in text; shown are lateral and dorsal views). 75) O. nubis, El Salvador (SRS #4803); 76) O. gala, Michoacán, Mexico (GTA #14065); 77) O. brockorum, Sonora, Mexico, paratype (SRS #1852); 78) O. nakamura, Costa Rica, holotype (GTA #14033); 79) B. idothea, Costa Rica (ADW #97-102); 80) B. rolla, Costa Rica (GTA #14055); 81) B. benito, Oaxaca, Mexico (SRS #4468); 82) B. mellanaformis, Costa Rica, paratype (GTA #14031); 83) L. librita, Veracruz, Mexico (GTA #14135); 84) N. heras, Guerrero, Mexico (ADW #97-112); 85) N. armandoi, Oaxaca, Mexico, holotype (GTA #14143); 86) N. isabelae, Guatemala, paratype (ADW #98-15).