by Steven J. Cary
Skippers (Hesperiidae). About a third of our butterfly fauna, ~110 species, belongs to this family, which is arranged into six subfamilies: Eudaminae, Pyrrhopyginae, Pyrginae, Heteropterinae, Hesperiinae and Megathyminae. Skippers earned their name because of their rapid, skipping flight, which is powered by a heavily-muscled thorax. All skippers have antennal clubs that are distinctively bent, curved or hooked. Larvae silk leaves together for nests; larvae hibernate over winter. Most subfamilies have distinct larval food preferences.
Spread-Wing Skippers (Hesperiidae: Pyrginae). About a third of New Mexico’s skipper species (33) are in this subfamily, which is also informally known as the “Herb, Shrub and Tree Skippers.” Larvae in this group eat a variety of dicotyledonous plants (herbs, shrubs and trees) in various families. The Pyrginae includes some genera whose member species have confusingly similar appearances, including the duskywings (Gesta species) and checkered skippers (Pyrgus and Burnsius). Identification is often challenging for Pyrgine skippers because key diagnostic characters are on wing undersides, which are hard to see when wings are spread, as they often are. For a few species, only genitalic examination via microscope can provide certainty regarding identity.
- Common Sootywing (Pholisora catullus)
- Mexican Sootywing (Pholisora mejicanus)
- Gold-headed Scallopwing (Staphylus ceos)
- Mojave Sootywing (Hesperopsis libya)
- Saltbush Sootywing (Hesperopsis alpheus)
- Texas Powdered-Skipper (Systasea pulverulenta)
- Arizona Powdered-Skipper (Systasea zampa)
- Common Streaky Skipper (Celotes nessus)
- Grizzled Skipper (Pyrgus centaureae)
- Mountain Checkered-Skipper (Pyrgus xanthus)
- Small Checkered-Skipper (Pyrgus scriptura)
- Common Checkered-Skipper (Burnsius communis)
- White Checkered-Skipper (Burnsius albescens)
- Desert Checkered-Skipper (Burnsius philetas)
- Tropical Checkered-Skipper (Burnsius oileus)
- Erichson’s White-Skipper (Heliopetes domicella)
- Northern White-Skipper (Heliopetes ericetorum)
- White-Patched Skipper (Chiothion georgina)
- Brown-Banded Skipper (Timochares ruptifasciata)
- Dreamy Duskywing (Erynnis icelus)
- Sleepy Duskywing (Erynnis brizo)
- Mottled Duskywing (Gesta martialis)
- Pacuvius Duskywing (Gesta pacuvius)
- Juvenal’s Duskywing (Gesta juvenalis)
- Rocky Mountain Duskywing (Gesta telemachus)
- Meridian Duskywing (Gesta meridianus)
- Horace’s Duskywing (Gesta horatius)
- Mournful Duskywing (Gesta tristis)
- Scudder’s Duskywing (Gesta scudderi)
- Funereal Duskywing (Gesta funeralis)
- Afranius Duskywing (Gesta afranius)
- Persius Duskywing (Gesta persius)
Pholisora catullus (Fabricius) Common Sootywing
Description. Common Sootywing is uniform glossy black above; the underside is glossy dark brown. The upperside has a variable number of white spots, mostly in the forewing subapical area. It can be distinguished from the next species only by looking at the hindwing underside. Range and Habitat. This skipper inhabits disturbed areas across most of temperate North America and into Mexico. In New Mexico it lives almost statewide (all counties except LA,SJ, but eventually it will be found there, too) below 7000′ in Upper Sonoran Zones. Life History. Larvae eat various species of Chenopodiaceae and Amaranthaceae such as Amaranthus retroflexus, A. blitoides, A. albus and Chenopodium album (Scott 1992). Many plants in these families are weeds in New Mexico, which makes disturbed areas good places to find this species. Flight. There are one to three generations annually in New Mexico. Peak flight is June to September in northern New Mexico, then May and August farther south; records span March 12 to November 26. Adults skitter and dodge near the ground seeking nectar and moist soil. Males patrol swales and arroyos looking for females. Comments. On 8 June 1981, several miles west of Portales (Ro), C. G. Schmidt observed several flying when air temperature was 104º F.
Pholisora mejicanus (Reakirt) Mexican Sootywing (updated December 8, 2020)
Description. Mexican Sootywing is a dead ringer for Common Sootywing, except for the ventral hindwing, which is iridescent steel blue with black veins. The iridescent, gun-metal blue fades to brown over time, but the black veins always stand out. Range and Habitat. Pholisora mejicanus appears to be restricted to the eastern foothills of the Rocky Mountains from southern Colorado south to Mexico, including central New Mexico (counties: Be,Co,Ed?,Li,Ot,Sv,SM,SF,So,To,Un). Like Pholisora catullus, it occupies disturbed, weedy areas in Upper Sonoran to Transition Zones, 6500 to 9200′. It prefers higher elevation areas compared to Pholisora catullus, which is rarely seen above 7000’ elevation. Life History. Larval hosts are shared with Common Sootywing, including Amaranthus retroflexus and Amaranthus blitoides. Flight. Adult flight habits are similar to those of Common Sootywing. It is univoltine to bivoltine in New Mexico. Peak flight is in July, but observations range from May 15 to August 27. Comments. It is not clear why Mexican is so restricted while Common is so widespread. They rarely occur together in New Mexico, but when they do, they do not interbreed. Their larvae can even occur on the same plant. Genomic data confirms these two species have been distinct for a long time. Dorsal similarity to Common Sootywing is blamed for several dubious determinations of Mexican Sootywings over the years.
Staphylus ceos (W. H. Edwards) Gold-Headed Scallopwing
Description. Its combination of orange head and palpi, habitat, and flight habits easily set Gold-Headed Scallopwings apart from all other New Mexico butterflies. Range and Habitat. Staphylus ceos lives in Mexico and the southwestern US, including southern parts of California, Arizona, Texas and New Mexico. Here it occurs in canyons, arroyos, and river valleys (counties: Be,Ca,DA,Ed,Gr,Hi,Lu,Ot,Si), 4000 to 6500′. Life History. According to Bailowitz and Brock (1991), Staphylus ceos larvae make nests and eat at least two species of Chenopodium (Chenopodiaceae) in southeast Arizona, including Chenopodium fremontii, which also is used in southern New Mexico. Flight. Adults fly near the ground, dodge through gnarly shrubs, perch at moist earth or low plants, and nectar at flowers. We have two broods per year, with adult flights peaking in April and August. Actual reports span the period March 14 to September 25. Comments. The first New Mexico report is attributed to Harry Clench, from Sitting Bull Falls, Guadalupe Mountains (Ed), on 12 September 1960.
Hesperopsis libya (Scudder) Mojave Sootywing (updated March 23, 2021)
Description. Dorsally, Mojave Sootywing looks like a Pholisora species; it is small and dark with subapical white spots on the forewing. The hindwing below, however, is olive-brown with a few white spots and the wing fringes are white. Range and Habitat. This skipper inhabits Lower Sonoran to Upper Sonoran Zone desert washes and alkali flats where the hostplants grow. It is distributed from northwest Mexico through the Great Basin north to Oregon, and on the east side of the Rockies as far north as North Dakota. It prefers lower altitudes below 5000′ and so barely reaches into NM along the Colorado River. We know of only one report (county: SJ), although it may be more widespread in an area that is little investigated by butterflers. Life History. Larvae eat Chenopodiaceae such as the widespread Four-wing Saltbush (Atriplex canescens); Atriplex confertifolia is also a suspected host (Scott 1986). Flight. Adults fly in low areas near larval hostplants and are fond of nectar. Our only report is for June, 4 miles northwest of Newcomb (Kilian Roever). There should be two broods per year if it is a breeding resident. Comments. Our populations belong to subspecies Hesperopsis libya confertiblanca (J. Scott).
Hesperopsis alpheus (W. H. Edwards) Saltbush Sootywing
Description. Saltbush Sootywing is marked like a diminutive Erynnis species, with nondescript smudges, marks and mottling that are hard to put into words. Wing fringes are checkered. Range and Habitat. This skipper inhabits southwestern deserts, ranging from Nevada, Utah and Colorado south into Mexico. In our state it occupies low and middle elevation areas (3000’ to 7300′), sometimes higher, but always with stands of the host (counties: Be,Ch,Ci,Co,DB,DA,Ed,Gr,Hi,Lu,MK,Ot,RA,Sv,SJ,SF,Si,So,Ta,Va). Life History. Various Chenopodiaceae serve as larval hosts. Fourwing Saltbush (Atriplex canescens) is thought to be the primary host in New Mexico. Flight. Like the other sootywings, adults fly weakly, though elusively, near the ground, almost always near stands of the host. They sometimes seek nectar. In New Mexico there is one mid-summer brood at relatively high altitude and high latitude. Hesperopsis alpheus is bivoltine at lower and warmer sites, with peak numbers in April to May and again in July. Extreme flight dates are March 9 and August 19. Comments. The type locality of Hesperopsis alpheus, described in 1876, is southwest of Raton (Co). In nearly 150 years since the types were collected, there have been no additional observations from within 100 miles, even though the larval host is common there. Our populations are assigned to the nominate subspecies.
Systasea pulverulenta (R. Felder) Texas Powdered-Skipper
Description. Our two Powdered-Skipper species have softly scalloped wing margins that distinguish them from other butterflies. Separating the two Systasea species from each other, however, is more challenging. The best character to check is the hyaline (translucent) spot band that traverses the forewing: on Systasea pulverulenta, the inner edge of this spot-band makes a smooth, uninterrupted curve. This species also has a pinkish cast dorsally when held at an angle to the light. Range and Habitat. Ranging from Central America to south Texas southern Arizona, Texas Powdered-Skipper also occurs in southeast New Mexico (counties: Ed) in low, thorny, hot arroyos. Life History. Nothing is known about its bionomics in New Mexico. In Texas, a variety of mallows (Malvaceae) are the larval hosts. Flight. This skipper flies almost year-round in south Texas, and is probably bivoltine in southeast New Mexico. Males establish territories and patrol arroyo bottoms. Comments. There are two valid New Mexocp record of Systasea pulverulenta, both from Eddy County, between 2 and 19 August. It may be more common here than records suggest, but few butterfliers venture into this species’ uninviting habitat, especially in August.
Systasea zampa (W. H. Edwards) Arizona Powdered-Skipper (updated January 28, 2021)
Description. This is the more widespread of our two Systasea species in New Mexico. Compared to Texas Powdered-Skipper, the median row of hyaline spots on the forewing has an irregular inner margin and the dorsal wing surface has a faint olive cast. Range and Habitat. Arizona Powded-Skipper has a more western distribution than Systasea pulverulenta. It lives in northwest Mexico, west Texas, and southern parts of California, Nevada, Arizona and New Mexico (counties: Ca,DA,Ed,Gr,Hi,Lu,Ot,Si). In our state it inhabits Upper Sonoran Zone canyons and foothill washes of desert mountains, usually 3600 to 6000′. Life History. For southeast Arizona, Bailowitz and Brock (1991) reported several larval hosts in the Malvaceae: Herrisantia crispa, Abutilon malacum, A. incanum, A. parishii, A. abutiloides, A. sonorae, and A. reventum. These are probable hosts in southwest New Mexico as well. Flight. A spring flight peaks in April, followed by overlapping broods from July to October. Records span March 6 to October 11. Males patrol canyon bottoms and arroyos, occasionally perching on rocks and low vegetation. Adults nectar and feed at moist arroyo sand. Comments. Our first record is from San Augustin Pass, Organ Mountains (DA), 27 April 1959 (Dr. John M. Burns).
Celotes nessus (W. H. Edwards) Common Streaky-Skipper
Description. This small species is unique among New Mexico butterflies, at least until Celotes limpia Burns, is found here. Celotes nessus is bronze with streaks of copper, gold, silver and dark brown above and below. Range and Habitat. It is an Upper Sonoran Zone dweller in our state (counties: Ca,Ch,DB,DA,Ed,Gr,Gu,Ha,Hi,Li,Lu,Ot,Qu,SM,Si,So,Un). It occurs from Arizona to Okloahoma then south into Mexico. All our records are from below 6300′ elevation. Life History. Larval hosts include Malvaceae (mallows) such as Abutilon incanum, Sida filipes, Wissadula amplissima, W. holosericea, and Sphaeralcea angustifolia var. lobata. Ayenia compacta (Sterculiaceae) is used in southern AZ; a female oviposited on Ayenia insulicola at Rockhound State Park (Lu) (Jim Brock). Flight. Adults fly near the ground in desert arroyos and canyons. Males patrol up- and down-stream from perches in dry streambeds, sometimes seeking nectar. It is bivoltine in most of New Mexico, with flight peaks in April to May and again in August. Extreme flight dates are March 6 and September 15. Comments. Common Streaky-Skipper has been seen along the Dry Cimarron River (Un) and may someday be found in Colorado.
Pyrgus centaureae (Rambur) Grizzled Skipper (updated January 29, 2021)
Description. All Pyrgus species are dark gray above, checked with white. Grizzled Skippers have a uniquely yellowish cast and no white spot at the base of the dorsal forewing cell. Ventral hindwing bands are more contrasty than on sister species in the genus. Range and Habitat. Grizzled Skipper’s arctic/alpine habitat enables it to prevail across Canada, Alaska and northern Asia. Colonies left behind after Pleistocene ice ages survive in the higher Rocky Mountains as far south as northern New Mexico (counties: Co,Mo,RA,SM,SF,Ta), where it lives near and above treeline, from 10,000’ to 12,500′ elevation. Life History. Larvae eat Rosaceae. Scott (1986) reported oviposition on Potentilla diversifolia. Like many tundra butterflies, Grizzled Skippers are biennial: two years are required to complete one generation. Flight. Adults are on the wing between June 5 and August 24, mostly late June and July. Look for them in damp meadows near treeline. Comments. While on the faculty of the Las Vegas Normal School, naturalist and Professor Theodore Dru Allison Cockerell found this species at 11,500′ near Spring Mountain (SM), 1-4 August 1900. Our populations belong to Rocky Mountain subspecies Pyrgus centaureae loki Evans.
Pyrgus xanthus W. H. Edwards Mountain Checkered-Skipper (updated January 29, 2021)
Description. This and the next species are tiny and hard to distinguish from each other. Mountain Checkered-Skipper has bolder contrasting marks; the hindwing above has a white basal dot and strong white bands. Bold black checks on the hindwing fringe extend all the way to the edge. The hindwing underside also is more boldly marked. Range and Habitat. Pyrgus xanthus is a Transition and Canadian Zone resident, frequenting pine forest openings in Colorado, Arizona and New Mexico (counties: Ca,Ch,Ci,Co,Li,LA,MK,Mo,Ot,RA,Sv,SM,SF,So,Ta), 6600 to 9800′. Life History. Larvae eat Potentilla species (Rosaceae). Scott (1992) reported oviposition on Potentilla pulcherrima at Hopewell Lake (RA) and on Potentilla subviscosa at Ledoux (Mo). He reported pre-oviposition on Potentilla ambigens at Cloudcroft (Ot) and adults associating with Potentilla hippiana and Potentilla pennsylvanica north of Raton (Co). Flight. This skipper completes one brood per year with adults about from March 25 to June 26, primarily in May. Males fly near the ground or patrol about the host. Both sexes bask on sunny rocks, visit moist soil, and nectar at flowers of the larval host. Comments. This species is easily confused with Pyrgus scriptura; the strongly checked hindwing fringe is a good character for separating the two.
Pyrgus scriptura (Boisduval) Small Checkered-Skipper (updated January 29, 2021)
Description. Pyrgus scriptura is even smaller than Pyrgus xanthus. The hindwing fringe is weakly checked: the dark vein-ends rarely reach the edge. Range and Habitat. Small Checkered-Skipper lives from the northern Rockies south to Mexico and west to California. In New Mexico, disjunct pockets of this skipper are found somewhat unpredictably in grassy savannas, along prairie watercourses, and in lowland arroyos (counties: Be,Ca,Ch,Ci,Co,DA,Ed,Gr,Ha,Hi,Li,Lu,MK,Mo,Ot,Sv,SM,SF,Si,So,Ta,To,Un), generally from 3300 to 8000′ elevation. Life History. Scott (1986) reported Sida hederacea, Sphaeralcea coccinea (in Colorado) and Sphaeralcea ambigua (all Malvaceae) as larval hosts. Flight. This species has variable voltinism in New Mexico. Records span March 1 to October 15. In north-central New Mexico there are overlapping broods from April to October, peaking in June. Southern New Mexico has flight peaks in March to April, June and August. Adults fly near the ground, pause at wet sand and seek nectar. Comments. Novelist/lepidopterist Vladimir Nabokov collected butterflies in New Mexico in 1954. A male Pyrgus scriptura taken near Eagle Nest on 23 June survives from that visit (Andrew Warren, pers. com.).
Burnsius communis (Grote), Common Checkered-Skipper & Burnsius albescens (Plötz), White Checkered-Skipper (updated January 29, 2021)
Description. On the underside of the hindwing, these two look-alikes have postmedian and postbasal bands of olive-tinted spots on a gray-white background, but they vary in expression from bold to faint. There are numerous white and dark gray checks on the upperside. Notably, the dorsal forewing usually lacks a white dot in the apex and in the small dark space beyond the hourglass-shaped white patch at the end of the discal cell. Fringes are evenly checked. Range and Habitat. As a ’complex’ this duo is ubiquitous in New Mexico, across most of temperate North America, and in the Neotropics. Burnsius albescens has the more subtropical range of the two, prevailing in southern New Mexico and below 5000’ elevation. Burnsius communis dominates farther north and up to 10,000′. Learning the full distribution of both forms will require collection and dissection of many specimens. Life History. Larvae eat many species of Malvaceae, including the genera Althaea, Abutilon, Anoda, Callirhoe, Hibiscus, Malvastrum, Modiola, Malva, Sidalcea, Sida and Sphaeralcea. Flight. Adults fly fast near the ground and visit nectar and water. Multivoltine, adults fly until severe cold sets in. New Mexico records span January 24 to December 14, concentrated in the warm season. Comments. These two taxa were only recently separated from each other in the laboratory by Smithsonian curator/researcher John M. Burns (Burns 2000). In long series, White Checkered-Skipper has a whiter dorsum than Common Checkered-Skipper, but field identification of individuals is impossible. Examine male genitalia to be sure of your catch: Burnsius albescens has one tooth on the valve, while Burnsius communis has two. Although separable in the laboratory, no work has been done with the live animals themselves to determine if they breed true in nature. It seems possible that that they could interbreed with impunity, not caring about that extra valve tooth. If you butterfly with binos or with a camera, consider them a complex of two and don’t worry about it. These and the next two species were formerly in the genus Pyrgus, but recent genetic work showed key differences which prompted erection in 2019 of the new genus Burnsius, appropriately honoring Dr. Burns.
Burnsius philetas (W. H. Edwards) Desert Checkered-Skipper (updated December 22, 2020)
Description. If one looks only at uppersides, this skipper is hard to distinguish from sister species Burnsius communis, Burnsius albescens and Burnsius oileus. To do so, look for a white dot at the dorsal forewing apex and a white spot beyond in the small dark space past the hourglass-shaped white patch at the end of the discal cell. The ventral hindwing, however, is distinctively white with only the faintest of ghostly dark marks, if you can get a view of it. Range and Habitat. Desert Checkered-Skipper occurs in Subtropical and Upper Sonoran Zone grassland habitats in Mexico, reaching its northern limits in southern Arizona, central Texas and southern New Mexico (counties: DA,Ed,Gr,Hi,Lu). In our state it is usually seen below 5500′ on grassy footslopes and adjacent arroyos draining desert mountains. Life History. Larval hosts are various Malvaceae. Bailowitz and Brock (1991) reported use of Sida procumbens. Flight. New Mexico records span March 16 to November 29. An early spring generation peaks in April; subsequent overlapping broods peak in September and October. Adults seek nectar and sip moisture from damp soil. Its flight is more subdued than that of White Checkered-Skipper, with which it can be easily confused based on uppersides alone. Getting that ventral view can be a challenge. Comments. This butterfly has been observed in the grasslands of City of Rocks State Park (Gr), which have not been grazed by domestic livestock since 1971.
Burnsius oileus (Linnaeus) Tropical Checkered-Skipper (updated January 30, 2021)
Description. Adult Tropical Checkered-Skippers are sexually dimorphic. Females are dark above, while males have a layer of white hairs. Both sexes have a dark area on the forewing fringe. Like Desert C-S, Tropical C-S has a white dot at the dorsal forewing apex and a white spot at the end of the forewing cell, both absent from the similar Common C-S and White C-S. Burnsius oileus has a boldly-patterned hindwing below and tends to be larger than the other Burnsius species. Range and Habitat. Tropical Checkered-Skipper lives in much of the Neotropics, including south Florida, south Texas and possibly southern Arizona, from where it may wander even farther north. In New Mexico it is a rare stray in Upper Sonoran riparian situations (counties: Gr,Hi). Life History. Larval hosts are Malvaceae such as Sida rhombifolia in Texas (Kendall 1976), but there is no evidence of reproduction in New Mexico. Flight. Our few records were logged between late March and late April. Burnsius oileus is likely to be multivoltine farther south, but it is only a stray here. Adults fly near the ground and come to nectar. Comments. Dale Zimmerman and P. Hoyt collected one below the mouth of Pacheco Canyon in the Gila River Valley on 31 March 1964 (det. C. D. Ferris). Paul Opler reported it from Eick’s Creek in the Animas Mountains (Hi), 27 April 91.
Heliopetes domicella (Erichson) Erichson’s White-Skipper (updated January 30, 2021)
Description. Though superficially like the various checkered-skippers, Erichson’s Wwhite-Skipper stands out with a bold, broad, white band crossing dark upper wing surfaces. Males and females are similar, but can be confused with female Northern White-Skipper. Range and Habitat. Heliopetes domicella is a Mexican skipper whose northern breeding limits are in southeast Arizona and west Texas. Strays are known from southern California, southern Nevada and southern New Mexico (counties: DA,Hi,Lu,Ot). Life History. Malvaceae (mallows) are the larval hosts. Larvae were found on Abutilon incanum and Herrisantia crispa in southeast Arizona (Bailowitz and Brock 1991). It is double-brooded there, with flights in spring and late summer. Flight. Our handful of records span March 8 to November 14, so it seems to be double-brooded in southern New Mexico, too. Adults patrol arroyo bottoms and come to nectar sources such as Apache plume. Comments. Some authors place this in the genus Heliopyrgus. Three Doña Ana County sightings over 2017-2018 suggest it may now be, or soon will be, breeding there.
Heliopetes ericetorum (Boisduval) Northern White-Skipper (updated March 15, 2021)
Description. This smallish skipper is sexually dimorphic. Males are white dorsally with black marginal hieroglyphics. Females have a white dorsal band across black wings like Erichson’s White-Skipper, but the band is more diffuse and the ventral forewing is white at its base. Range and Habitat. A widespread North American member of this genus, Heliopetes ericetorum ranges from eastern Washington south into Mexico. It lives in Upper Sonoran Zone (6000 to 7000′) canyons of the Colorado Plateau, including northwest New Mexico (counties: Ca,Gr,Li,MK,RA,SJ), where it is never common. Life History. Various Malvaceae and Sterculiaceae are larval hosts. Ovipositions on Sphaeralcea species are reported from southeast Arizona (Brock 1993). Flight. Our few reports suggest one generation peaking in June. Specific New Mexico records span May 22 to August 31. Males establish territories along gully bottoms. Adults come to nectar and water. Comments. The first New Mexico record of this species is credited to John Woodgate, who collected a male at Fort Wingate (MK) on 12 June 1910. The specimen is in the American Museum of Natural History.
Chiothion georgina (Reakirt) White-Patched Skipper
The ventral surface of this butterfly is white and the dorsal surface has white patches. White-Patched Skipper is a subtropical species that breeds from Argentina north to Mexico and south Texas. It may also breed seasonally in southern Arizona. It is prone to wandering, which accounts for the sole New Mexico report. Reported larval hosts are Malpighiaceae (Scott 1986), including Malpighia glabra, an ornamental plant cultivated in south Texas for its fruits, which are made into jellies (Kendall and Rickard 1976). Our one record is from Guadalupe Canyon (county: Hi) on 10 October 1989 by Kilian Roever. The late summer rainy season is the most likely time to encounter this unusual species. Adults prefer moist canyons and perch at mud puddles. This butterfly has been mistaken for Chiomara asychis (Stoll), a South American species with which its relationship is under study (see Opler and Warren 2002).
Timochares ruptifasciata (Plötz) Brown-Banded Skipper (updated January 30, 2021)
Like many Erynnis species, the upper side of Brown-Banded Skipper is tan with bands of brown spots paralleling the wing margins. Unlike many Erynnis species, there are no white spots and the ventral surface is orange-brown. This subtropical Mexican skipper apparently breeds in south Texas, where its larval host is an ornamental plant in urban areas, but it is merely a rare stray in southwest New Mexico (county: Gr). The reported larval host in Texas is Malpighia glabra (Malpighiaceae) (Kendall and Rickard 1976). Most of our infrequent subtropical strays are encountered during or shortly after the summer monsoon season. In this case, our solitary record is from 20 September 1963, caught by Dale Zimmerman at Little Walnut Creek, north of Silver City.
Erynnis icelus (Scudder & Burgess) Dreamy Duskywing
Description. Dreamy and Sleepy duskywings are very similar. The dorsal forewing of each has a chain-like postmedian row of gray spots, while lacking the translucent, hyaline white spots typical of most congeners. How do they differ? Erynnis icelus is smaller and has a broad wash of silver scales beyond the postmedian spot row on the dorsal forewing. It also has a restricted range, different behaviors and lives in different habitats. Males have a costal fold. Range and Habitat. Dreamy lives across Canada and southward, reaching southern limits in the mountains of Arizona and New Mexico (counties: Be,Ca,Ci,Co,Gr,Li,LA,Mo,Ot,RA,Sv,SJ,SM,SF,Si,Ta,To,Un). Here it likes Transition and Canadian Zone openings near aspen, 7000 to 10,000′ elevation. Life History. Scott (1992) witnessed oviposition on a seedling of quaking aspen (Populus tremuloides; Salicaceae) at Hopewell Lake (RA). That is the only known larval host here. Flight. Adults come readily to flowers and moist earth. They perch in forest openings looking for mates; males do not hilltop. Records span April 10 to July 25. Univoltine adults peak in May in the Sacramentos, but in June farther north. Comments. If aspen is part of your vegetation community, then you are in Dreamy Duskywing country.
Erynnis brizo (Boisduval & Le Conte) Sleepy Duskywing (updated January 30, 2021)
Description. Sleepy Duskywing closely resembles Dreamy, as discussed above, in having median and postmedian chains of gray spots on the dorsal forewing, but it lacks, Dreamy Duskywing’s broad silver wash of scales. It also is larger, lives in different habitats and exhibits different mate-location behaviors. Range and Habitat. Erynnis brizo lives in Upper Sonoran to Transition Zones throughout non-boreal Mexico and North America (all New Mexico counties). Its altitude range is 5200 to 7800′, but it will fly to higher hilltops. Life History. Larvae eat oaks (Fagaceae) including Quercus arizonica, Quercus undulata, Quercus havardii, Quercus gambelii and Quercus emoryi. Mature larvae overwinter. Flight. Sleepy Duskywings are univoltine with adults on the wing in spring, March 4 to July 23. Flight peaks occur in April in the south, in May on our northeast plains, and in June in the mountains. Males are eager hilltoppers, unlike Erynnis icelus. Adults visit moist earth and nectar at spring flowers such as Nolina, Ungnadia, Oxytropis and Rhus. Comments. Our populations are placed in subspecies Erynnis brizo burgessi (Skinner). Some July records may refer to the similar Ernnis icelus. This butterfly flies among the shinnery oak of the Mescalero Sands of southeast New Mexico.
Gesta martialis (Scudder) Mottled Duskywing (updated January 31, 2021)
Description. Mottled Duskywings have a mottled, contrasty dorsal forewing, rather like that of Rocky Mountain Duskywing or Afranius Duskywing. It stands out from these look-alikes with ventral hindwing submarginal spots that are much more elaborate and showy (for a duskywing). Range and Habitat. Gesta martialis is widespread in eastern North American woodlands and in the eastern, tallgrass Great Plains. Disjunct western colonies occur along the Rocky Mountain Front Range foothills from South Dakota as far south as northeast New Mexico, where they occupy Transition Zone savannas. Life History. Although little is known about this butterfly in New Mexico, Ceanothus fendleri (Rhamnaceae) is the larval host in Colorado (Ferris and Brown 1981) and probably in New Mexico, too. Flight. Rocky Mountain Gesta martialis is univoltine flying in June. Our one confirmed population flies at 8400′ elevation on the Raton Mesa volcanic complex (county: Co) from May 12 to July 4; one October 4 specimen suggests a second brood. Males hilltop; females associate with the larval host. Comments. The 1996 discovery of Gesta martialis in New Mexico does not legitimize a dubious report from the Sandia Mountains 50 years earlier (see Cary and Holland 1992).
Gesta pacuvius (Lintner) Pacuvius Duskywing
Description. Pacuvius has a distinctive dorsal forewing showing contrasty light brown and dark gray patches, like Mottled Duskywing or spring generation Horace’s Duskywing, with which it may fly. The white-fringed hindwing sets it apart from these congeners, but it creates confusion with Juvenal’s and Scudder’s duskywings in southwest New Mexico. Range and Habitat. Gesta pacuvius lives in the Rocky Mountains from British Columbia south into Mexico and Baja California. In New Mexico it inhabits Transition and Canadian Zone open woodlands in most major uplands (counties: Be,Ca,Ci,Co,Gr,Hi,Li,LA,MK,Mo,Ot,RA,Sv,SJ,SM,SF,Si,So,Ta,To), 7000 to 9200’ elevation. Life History. Fendler’s Buckbrush (Ceanothus fendleri; Rhamnaceae) is the larval host in New Mexico, Arizona and Colorado. This plant is a fire climax plant. It thrives in a frequent-fire landscapes because its seeds, which accumulate in soils beneath the plant, can germinate only after fire melts off the paraffin coating, allowing water to penetrate. Flight. Pacuvius is uni- to bivoltine here. In southwest New Mexico the two generations are strong and distinct, with peaks in April and August. The two broods overlap in intervening areas. Our north-central mountains have peak flight in June to July. Overall, New Mexico records fall between April 1 and September 5. Males hilltop, but both sexes will come to nectar, scat and moist soil. Comments. Pacuvius was described in 1876 from material collected at some unspecified New Mexico location by the Wheeler Expedition. Our populations belong to the nominate subspecies.
Gesta juvenalis (Fabricius) Juvenal’s Duskywing (updated January 31, 2021)
Description. Gesta juvenalis is hard to decipher from the crowd of southwestern duskywings with white hindwing fringes. The forewing above has a row of pale postmedian spots again a dark submargin. It is less contrasty above and larger than Gesta pacuvius, and larger than Gesta scudderi. The forewing is less pointy than Gesta funeralis. The hindwing below lacks the white marginal patches of Gesta tristis tatius. Most of these ‘differences’ are nuanced, making field determinations, even photo IDs, challenging. Genitalic determination is recommended in most cases, and that, of course, requires a specimen. Range and Habitat. Juvenal’s Duskywing is widespread in eastern North America with an outpost in west Texas. A disjunct Mexican population extends north along the Sierra Madre Occidental into southeast Arizona and southwest New Mexico (counties: DA?,Hi,Lu?), where it is an Upper Sonoran to Transition Zone resident, 4500 to 8000′ elevation. Life History. Larval hosts are oaks (Fagaceae). Quercus arizonica, Quercus emoryi and Quercus grisea are reported from southeast Arizona (Burns 1964) and are probably used in southwest New Mexico as well. Flight. We have two broods per year. Our records span March 18 to May 29 and July 14 to August 3. Males hilltop, but not strongly. Comments. The geographic race in our area is subspecies Gesta juvenalis clitus (W. H. Edwards). The nominate eastern race lacks the white hindwing fringe. As suggested by the uncertainty regarding reports from Dona Ana and Luna counties, a paucity of observations and observers in our southwestern quadrant hampers our ability to better understand this butterfly in New Mexico.
Gesta telemachus Burns Rocky Mountain Duskywing (updated January 31, 2021)
Description. Rocky Mountain Duskywing is large with a gray dorsal forewing contrasting with the brown dorsal hindwing and brown wing fringes. The other similarly two-toned species, Persius and Afranius, are smaller. The dorsal forewing has hyaline spots in the median area, but so do other duskywing. The 1-2 pale dots at the ventral hindwing apex is the best diagnostic character, shared only by Gesta juvenalis clitus, whose white fringe sets it apart. Range and Habitat. This skipper lives in the central Rocky Mountain states of Utah, Colorado, Arizona and New Mexico (all counties but Cu,DB,Gu,Hi,Le,Qu,Ro). It inhabits Transition Zone oak openings with the host, 5000 to 9000′ elevation. Life History. Gambel’s Oak, (Quercus gambelii; Fagaceae), is the host for Rocky Mountain Duskywing. A female oviposited on expanding buds of an oak at Alps Mesa (Un) on 5 May 1996 (S. Cary). Eggs hatch quickly and larvae eat developing spring tissues. The strong representation of Gambel Oak in the flora of the Four Corners states causes its herbivore, Rocky Mountain Duskywing, to have an equally strong presence, for its size. Flight. Gesta telemachus is single-brooded and the timing of its flight is an aid in identifying it. Adults fly in spring between March 22 and July 22; timing of the peak flight depends on altitude and latitude. Adults perch, patrol, bask and nectar in swales or drainages near stands of the larval host. Comments. This species languished in anonymity until Burns (1960) teased it out of the duskywing tangle. It had been collected around the Rockies for decades, but for lack of a better option it had been reported as Gesta juvenalis, Gesta martialis and Gesta propertius.
Gesta meridianus E. Bell Meridian Duskywing (updated January 31, 2021)
Description. Meridian Duskywing may be confused with the summer brood of Horace’s Duskywing, but it has less contrasting marks. Fortunately, their area of geographic overlap, or sympatry, is small. Meridian’s upperside is dark gray and dark chocolate, sprinkled with tiny translucent postmedian white dots. Above and below, the hindwing has iridescent dark submarginal dots on an iridescent light brown background. The hindwing fringe usually is dark with white scale-tips. Spring brood tend to be smaller and not as dark. Range and Habitat. Gesta meridianus lives in Nevada, Utah, Arizona, Texas and southern New Mexico (counties: Be,Ca,Ch,Co,DA,Ed,Gr,Gu,Ha,Hi,Li,Lu,Ot,Sv,Si,So,To,Un,Va) south to Mexico. It inhabits oak woodlands from 4500 to 7000′, hilltopping to 8500’ elevation. Life History. Larvae of Meridian Duskywings eat evergreen oaks (Fagaceae) such as Quercus arizonica and probably Quercus grisea and others. Flight. Males patrol desert hilltops, often quarreling with Mournful Duskywing males for the best spots. Both sexes come to nectar and water. New Mexico records of this bivoltine skipper are known from March 11 through September 19, with peak numbers in April and August. Comments. Rare dwarf individuals turn up in extreme southern New Mexico (Ed,Hi). They are the size of Gesta persius and hilltop like that species, but they have Gesta meridianus genitalia (J.A. Scott and R.E. Stanford, pers. comm.). It is called Southwestern Oak Duskywing in some books.
Gesta horatius (Scudder & Burgess) Horace’s Duskywing (updated January 31, 2021)
Description. Horace’s Duskywing resembles Meridian Duskywing. Spring brood Horace’s have contrasting tan and gray patches on the forewing above. Summer brood Horace’s may be iridescent chocolate brown. Translucent hyaline dots on the dorsal forewing are larger on Horace’s than those on Meridian. Hindwing iridescent submarginal spots are prominent. Range and Habitat. This eastern US species has a disjunct population in the southern Rockies and Southwest. It occupies Upper Sonoran and Transition Zone oak woodlands in New Mexico usually from 5000 to 8000’ elevation (counties: Co,Ed?,Gu,Ha,Li,LA,Mo,Ot,Qu,RA,Sv,SJ,SM,SF,So?,To,Un). Life History. Larvae eat oaks (Fagaceae) such as Quercus gambelii and Quercus undulata in New Mexico. Larvae roll leaves into nests, then overwinter. Flight. Gesta horatius is bivoltine. Statewide records fall between April 4 and October 4. Adults seek nectar; males may hilltop. Comments. The Sacramento Mountains have a strong spring flight from April to May with a weak July flight. The north-central mountains and eastern plains have a weak spring brood, but a strong July flight. Scant, unverified reports from Eddy and Socorro counties probably represent misidentified Meridian Duskywings.
Gesta tristis (Boisduval) Mournful Duskywing (updated January 31, 2021)
Description. Mournful Duskwings have a unique combination of a white hindwing fringe and elongated white patches along the ventral hindwing margin. Rarely absent, these patches are the best way to separate them from other white-fringed duskywings. You just have to get a look at the underside. Range and Habitat. Nominate Gesta tristis is Californian. Our population is disjunct and distinct, occurring from Arizona, west Texas and southern New Mexico (counties: Ca,Ch,DA,Ed,Gr,Gu,Hi,Li,Lu,Ot,Si,So) south to Colombia. Mournful Duskywings live in Upper Sonoran Zone oak woodlands from 4500 to 6500′ elevation. Conveniently, Gesta tristis and Gesta horatius are nearly allopatric in New Mexico, which simplifies field identifications. Life History. Oaks (Fagaceae) are the larval hosts. Specific oaks used in our region are unknown, but Quercus grisea is suspected and other species are also likely. Flight. Mournful males establish hilltop territories by defending perches atop the tallest vegetation on summits, usually oaks or junipers. Females frequent nectar and water. Our records suggest two generations per year: March 15 to May 23 peaking in April, and again June 22 to October 9 peaking in August. Comments. We have white-fringed, southwestern version: Gesta tristis tatius (W. H. Edwards). Kansas Professor Francis Huntington Snow caught the first New Mexico specimen in Water Canyon in the Magdalena Mountains (So) in August 1881. It was as yet undescribed by science and he reported it, erroneously, as Gesta funeralis. Granted, he may have been distracted by his hair-raising escape from local Apaches who objected to his intrusion into their lands. William Henry Edwards described this ‘white-fringed’ subspecies in 1883 from specimens collected at Mount Graham in Arizona.
Gesta scudderi (Skinner) Scudder’s Duskywing (updated March 11, 2021)
Description. Positive identification of individual Scudder’s Duskywing requires genitalic dissection and examination. This species is smaller than Gesta juvenalis clitus and not as contrasty as Gesta pacuvius, but its resemblance to each is such that naked-eye determinations are suspect unless many individuals can be compared. Range and Habitat. This Mexican species barely edges into the US along the Sierra Madre in southeast Arizona and southwest New Mexico (county: Hi), where it occupies Upper Sonoran to Transition Zone scrubby woodlands. Life History. Little is known of its bionomics, but the likely larval hosts for Gesta scudderi are oaks (Fagaceae). Flight. Bailowitz and Brock (1991) indicate two annual generations in southeast Arizona. Our one record is from 4 March 1986, when it was captured at Geronimo Pass in the Peloncillo Mountains by Ray E. Stanford. Its identity was confirmed by J. A. Scott and H. A. Freeman. Comments. Because of difficulty in identification, Gesta scudderi may be more common in southwest New Mexico than the one confirmed record suggests.
Gesta funeralis (Scudder & Burgess) Funereal Duskywing
Description. Funereal Duskywing’s long, narrow forewing is unique among the Duskywings in our area. A distinctive dorsal forewing tan patch occurs just inside of the subapical white spots. The hindwing is fringed with white. Range and Habitat. Gesta funeralis breeds in Upper Sonoran Zones of Central and South America, Mexico and the southwest US, including much of New Mexico. Its widespread occurrence here (all counties but DB,Ro) is the result of strays wandering north and breeding seasonally. Life History. Many legumes (Fabaceae) are larval hosts. The author observed oviposition on New Mexico locust (Robinia neomexicana) in the Sacramento Mountains (Ot). Polyphagous and multivoltine, our most widespread white-fringed duskywing has been found from 3,900 to 11,200′. Flight. Influx of adults and seasonal breeding help Funereal Duskywings maintain steady levels in most southern New Mexico summers. Records span March 15 to October 24. Adults wander along drainages, feeding at nectar or mud. Comments. Some experts consider Funereal to be a subspecies of Gesta zarucco (Lucas), a species of coastal southeastern North America. Funereal Duskywing was considered a resident of southern New Mexico and only a rare stray to northern areas as recently as 2000. Since then it has become almost routine in northern New Mexico, too.
Gesta afranius (Lintner) Afranius Duskywing (updated February 3, 2021)
Description. Afranius and Persius (the next species) are similarly small and difficult to differentiate. They both have dorsal forewing subapical white spots. Gesta afranius males lack the numerous whitish hairs blanketing the dorsal forewing of Gesta persius males. Females and worn males may require genitalic determination. Range and Habitat. Afranius Duskywing lives throughout the Rockies and high plains from southern Canada south to the Mexican Sierra Madre. In New Mexico it prefers canyons and ravines in Transition Zone savannas, generally 6000 to 9000’ elevation (counties: all except Ci?,DA,DB,Ed,Hi?,Le,Lu,Ot?,Ro,Va). Life History. Larvae eat a variety of legumes (Fabaceae). The widespread Lupinus argenteus is popular in northern New Mexico. Hosts in nearby states include Lupinus caudatus and Thermopsis divaricarpa (Scott 1992), as well as Lotus wrightii (Brock 1994). Flight. The two annual broods produce peak adult numbers in April and July. Flight dates span March 23 to August 16. Males patrol low areas; both sexes seek nectar. Comments. In the field, Afranius can sometimes be separated from Persius based on habitat. If you look around and see lupines, you should suspect Afranius. If you see Golden Banner (Thermopsis diaricata), it is probably Persius. This generalization fails in some places (see Scott 1992). Uncertainty regarding reports from Cibola, Hidalgo and Otero counties reflect unresolved confusion with Gesta persius, for example they may be photographs or undissected female specimens.
Gesta persius (Scudder) Persius Duskywing (updated February 3, 2021)
Description. Smallish, Persius Duskywing is much like Afranius Duskywing, but fresh males have a dense blanket of whitish hairs on the dorsal forewing. Hindwing pale spots usually are more distinct than on Afranius. Use of these characters is possible if one can determine sex and if individuals are in good condition. Males (small abdomen) tend toward gray above, while females (larger abdomen) tend toward brown. Females and worn males may require genitalic determination. Range and Habitat. Gesta persius occurs in the northeast US and in the western US cordillera from Alaska south to montane Arizona and New Mexico (counties: Be,Ca,Ci,Co,Gr,LA,Mo?,Ot,RA,Sv,SJ,SM,SF,Si?,Ta,To,Un). Its habitat is somewhat more alpine than that of Gesta afranius. Life History. Persius uses several hosts for its larvae. In the West it prefers legumes (Fabaceae) such as Astragalus flexuosus, Thermopsis divaricarpa and sometimes Lupinus argenteus. Oviposition has been observed on Thermopsis species (RA) (Scott 1992) and on Astragalus species (Ta). Mature larvae hibernate. Flight. Persius Duskywing males patrol hilltops, which is different from gully-patrolling Afranius males. There is one generation per year, perhaps with a partial second brood in southern New Mexico. Persius flies mostly from May to July. Reports from March and September are likely to be misidentified Afranius. Comments. Reports from Mora and Sierra counties remain uncertain due to identification difficulties. The McCauley Expedition collected Persius along the Rio Chama southwest of Ojo Caliente (RA), on 7 July 1877.