Amblyscirtes hegon, IN (Scudder, 1863) IN

AMBLYSCIRTES ‘ HEGON ’ IN LITERATURE

Amblyscirtes hegon has historically been recognized as a single species. The current analysis views previously published life history accounts as broadly applying to a complex of four newly-identified species under the guise of “ hegon ”. The following sampling of literature treatments provides us with a general guide to the life histories of various populations, but cannot be reliably attributed to any of the four species revealed in this study. The butterfly is generally described as uncommon, though occasionally being found in numbers. A review of morphological descriptions, as follows below, focuses on the ventral hindwing ground color, which is the most revealing (though variable) character that we have found, to differentiate the species. All populations of the hegon complex bear similar lightly colored markings set against a dark ground color, especially the highly variable arc of light marks across the ventral hindwing, as well as checkered wing margins. Interestingly, the ventral hindwing is often described as “greenish” or “greenish-gray”, based primarily on the effect of the peppering of pale scales set against the darker ground color. This greenish look is more the result of human perception. The greenish appearance apparently fades in collections ( Forbes, 1960), but color analysis reveals a different ventral color relationship, based on collected specimens of varying ages. Interestingly, not one of the published images in the literature, nor in 900 images on inaturalist.org, butterfliesandmoths.org, or butterfliesofamerica.com show the reported “greenish” appearance of the ventral hindwing; just varying degrees of gray peppering on a variable brown background. The reference to “green” in later works might simply be a repeat of earlier works subject to visual misinterpretation ( Fernald, 1884; French, 1886; Scudder, 1889). [One of us (Pavulaan) previously worked at a printing company, where a cost-saving “green” print was made by combining yellow with gray. This combination might account for the apparent “green ” look View in CoL of the underside of the wings, where pale, yellowish scales overlay a grayish ground color.]

The hegon complex is generally reported to be univoltine throughout its range, flying from March (Gulf Coast region) to July (Canadian Maritimes), but there are curious reports of possible second-generation individuals in August in Connecticut (O’Donnell, et al., 2007), Massachusetts ( Stichter, 2015), and North Carolina ( Glassberg, 1999; LeGrand & Howard, 2023), and even into September in Missouri ( Heitzman & Heitzman, 1987). This requires future investigation and may reveal either an extended univoltine flight of any of the four taxa in the hegon complex into August in some places, or a partial second brood. Essentially, little is known of the hostplant choices of the four species in the hegon complex. Several hosts have been identified for ‘A. hegon’, but most published works simply appear to repeat earlier lists, including some which are certainly in error. More fieldwork is needed here as well. The only images of the larvae we have found are those shown in Allen (1997), Allen, et al. (2005), and Venable (2014).

William F. Kirby (1871) applied line priority, treating Hesperia hegon View in CoL as a species over H. samoset View in CoL . No life history information was given.

Charles H. Fernald (1884) listed this butterfly as A. samoset . The underside is described as “lighter than above, and heavily overlaid with greenish scales.”

George H. French (1886) listed this butterfly as A. samoset . The underside is described as “lighter than the upper, overlaid with greenish scales…”

Samuel H. Scudder (1889), in his discussion of samoset at species rank, gave a rather detailed description of the adults. He describes the ventral color as “uniformly and profusely flecked with very pale greenish yellow scales, giving the wing a greenish gray appearance.” Life history information concerning the broods, immature stages and the host was based on the illustrations of John Abbot: “Nothing is known of the earlier stages but what may be gleaned from Abbot.” However, Calhoun (2019 and pers. corr.) convincingly stated that Abbot’s drawings depicted a well-marked Amblyscirtes alternata , as well as the immature stages and host of alternata : “Scudder…misidentified the butterflies in the DBC and HLHO drawings as the species now recognized as Amblyscirtes hegon .” Calhoun also stated: “While Abbot illustrated A. alternata many times, I found no evidence that he encountered A. hegon . ” Based on this misidentification, Scudder erroneously believed that samoset has two broods in the southern states.

Scudder identified the host grass in Abbot’s illustration as Sorghastrum avenaceum (Indiangrass) , now known as Sorghastrum nutans per the USDA PLANTS Database (https://plants.usda.gov/home/plantProfile?symbol=SONU2). [ S. nutans should be stricken from the record as a host of A. hegon , since Abbot’s image shows it associated with A. alternata .] Scudder stated: “In the Boisduval MS, it is given as Sorghum secundum .”, now known as Sorghastrum secundum (Lopsided Indiangrass) . However, Abbot’s original drawing of A. alternata depicts this grass accurately, matching the image of Sorghastrum secundum in the USDA PLANTS Database (https://plants.usda.gov/home/plantProfile?symbol=SOSE5). [Thus, S. secundum should also be stricken from the record as a host of A. hegon .]

Charles J. Maynard (1891) listed this butterfly as A. samoset . He described the underside as “brown, overwashed with whitish…”

William J. Holland (1898, 1931 [Revised Edition]) listed this butterfly as A. samoset . He described the underside as “pale gray”.

William F. Fiske (1901) listed this butterfly as A. samoset .

Harrison G. Dyar (1902) listed this butterfly as A. samoset , with hegon , nemoris and alternata listed as synonyms.

John H. Comstock & Anna B. Comstock (1912) listed this butterfly as A. samoset . The ventral surface of the wings is described as “being overlaid with greenish scales.”

James H. McDunnough (1938) listed this butterfly as A. hegon , with samoset and nemoris listed as synonyms.

Alexander B. Klots (1951) described the ventral hindwing of A. hegon as “heavily and coarsely dusted with light, greenish gray on a dark background.” He erroneously followed Scudder (1889) in description of the larvae and broods: “One brood in north, supposedly two southward”. The hostplant is given as “grasses”.

Harrison M. Tietz (1952, 1972) correctly assigned hegon to species rank, and listed samoset and nemoris as synonyms. Sorghum bicolor (as S. vulgare ) (Grain Sorghum ) is listed under food plants.

Douglas C. Ferguson (1954) listed hegon as occurring in Nova Scotia, occurring from May 31 to July 2, and being “scarce and local.”

William H. Evans (1955), citing Scudder (1889) as “first reviser”, treated samoset at species rank, and hegon as a synonym. Line priority of hegon over samoset in the original descriptions ( Scudder, 1863) shows this to be an erroneous treatment.

Bryant Mather & Katherine Mather (1958) list only two records for hegon , both from Tishomingo County in extreme northeast Mississippi. These would most likely actually be nemoris . The specimens of matheri were collected in southwest Mississippi after publication of this work and it’s three supplements.

William T. M. Forbes (1960) provided a rather enlightening taxonomic account under A. samoset : “The two names [referring to hegon and samoset ] were published together, and Scudder later chose samoset , as he then (and now) had a right to do; the use of hegon is based on a blind following of “page priority”. Forbes described the underside: “Below evenly dusted with pale yellow, giving a faint greenish effect when fresh (fading in a collection) …”

Cyril F. dos Passos (1964) listed samoset at species rank, with hegon , nemoris and argina as synonyms.

Lucien Harris, Jr. (1972) chose to refer to this as Amblyscirtes samoset . Flight dates in Georgia are April through May, but one July record is listed.

Roderick R. Irwin & John C. Downey (1973) listed samoset at species rank.

Auburn E. Brower (1974) correctly assigned hegon to species rank, and listed samoset as synonym.

Arthur M. Shapiro (1974) describes the flight of hegon as: “One brood, late vi-early vii, northward; partially double-brooded in Finger Lakes, vi.3-vi.20 and vii.22.”

C. Don MacNeill in William H. Howe (1975) described the ventral hindwing of A. hegon as being “heavily dusted with greenish gray scaling. The listed hostplants Sorghastrum nutans ( = avenaceum ) and S. secundum are, no doubt, cited from Scudder and are in error.

Bryant Mather & Katherine Mather (1976) interestingly changed the Mississippi listing of hegon to samoset . This would most likely actually be nemoris .

Lee D. Miller & F. Martin Brown (1981) listed hegon at species rank, with samoset , nemoris and argina listed as synonyms.

Robert M. Pyle (1981) described the ventral side of hegon as “putty gray with understated light spots; greenish cast over HW.”

Lee D. Miller & F. M. Brown in Ronald W. Hodges (1983) listed hegon at species rank, with samoset , nemoris and argina listed as synonyms.

Paul A. Opler & George O. Krizek (1984) described the ventral hindwing as: “dusted with light gray-green scales”. The habitat is described as “glades or at the edges of mixed or coniferous forest as well as at the edges of bogs or boggy streams.” The authors correctly state that “ hegon is univoltine throughout its range, but rare, late-emerging adults are occasionally found in late July [northern New York]”. The hostplants are given as Poa pratensis ( Kentucky Bluegrass), Sorghastrum nutans and Sorghastrum secundum [both likely in error as host of A. alternata ], and Uniola latifolia (Indian Woodoats) [now recognized as Chasmanthium latifolium (Indian Sea Oats) ].

Bryant Mather & Katherine Mather (1985) interestingly changed the Mississippi listing of samoset back to hegon . This would most likely actually be nemoris .

James A. Scott (1986) described the ventral hindwing as “greenish-gray.” The hostplants are given as Poa pratensis , Sorghastrum nutans and S. secundum [both likely in error as host of A. alternata ], and Uniola latifolia [now recognized as Chasmanthium latifolium ].

Ernest M. Shull (1987) described the ventral hindwing of hegon as “heavily dusted with greenish gray…”

J. Richard Heitzman & Joan E. Heitzman (1987) describe hegon as having “greenish-gray scaling of the wings beneath.” They described the brood sequence in Missouri: “Most specimens have been found in April and May, but there are June, July and September records, indicating at least partial broods during the summer.”

Paul Klassen, A. Richard Westwood, William B. Preston & W. Brian McKillop (1989) describe the underside of hegon as “dusted with pale gray…The veins on the underside of the hindwings are highlighted with whitish-gray…Most specimens have a greenish-gray hue on the underside of the wings.”

Paul A. Opler & Vichai Malikul (1992) described the ventral hindwing of hegon as “light gray-green”. The flight period is described as “April-July, rarely early Aug. (1 brood), earliest in the south.”

Jeffrey Glassberg (1993) described the underside as “yellowish tinged gray-brown ground…”

Thomas J. Allen (1997) described the underside as “brownish gray”. He describes the habitat preference as: “This skipper prefers wet areas and is found along streams, bogs, low-lying wet meadows, and glades at the edges of mixed or coniferous forests.” He correctly stated that hegon is univoltine throughout its range. The larvae is described as “pale green with 3 dark green dorsal stripes and a pale lateral stripe” and the host is given as Glyceria striata (Fowl Mannagrass) .

Ross A. Layberry, Peter W. Hall & J. Donald Lafontaine (1998) described A. hegon with the ventral hindwing as “grey, with a slightly greenish tinge that is most noticeable in fresh specimens…”

Paul A. Opler & Amy B. Wright (1999) described the ventral hindwing of hegon as “light gray-green”.

Jeffrey Glassberg (1999) described the underside as “olive-tinged gray-brown…” The brood sequence is given as “1 brood + partial second north to Virginia and Missouri-mid April- May, rare partial July-Aug.”

Mogens C. Nielsen (1999) described the underside of hegon as “grayish green.”

Jim P. Brock & Kenn Kaufman (2003) describe the ventral hindwing of hegon as “frosted greenish gray”. The brood sequence is described as “late spring (mainly) to summer in south (1-2 broods), early summer in north (1 brood).

Marc C. Minno, Jerry F. Butler & Donald W. Hall (2005) indicate a single hegon flight in Florida, and suggest the host as “probably” Glyceria striata . The larva is illustrated.

Jane O’Donnell, Lawrence Gall & David Wagner (2007) describe the underside in Connecticut specimens as “Wings below medium to dark brown with extensive gray frosting and fainter spots.”

W. Mike Howell & Vitaly Charny (2010) repeat previous host lists, including Poa pratensis and Chasmanthium latifolium . The listed hostplants Sorghastrum nutans ( = avenaceum ) and S. secundum originate from Scudder and are certainly in error. The authors indicate a single brood in Alabama, late March to late June.

John K. Bouseman, James G. Sternburg & James R. Wiker (2010) describe the venter of hegon as “…the anterior half of the forewing is dusted with gray-green scales. Similar scales extend over the entire hindwing.” The authors add Cinna arundinacea (Stout Wood Reed) to the list of hosts.

Jim Patterson (2011) identified hegon as “A very small dark gray skipper with greenish overtones on the ventral side.”

Peter W. Hall, Colin D. Jones, Antonia Guidotti & Brad Hubley (2014) described A. hegon with the underside as: “Both wings flecked with greyish-green when fresh, creating the “pepper and salt” effect. With age, the flecking wears away and the wings become more uniform dark brown.”

Rita Venable (2014) noted, regarding the ventral color of hegon : “…they start out gray and end up dark brown! Their gray scales just wear off with time.” This accurately describes the difficulty observers will have, differentiating the four species described in this work based solely on ventral ground color. The host listed for Tennessee is Chasmanthium latifolium (River Oats, or Indian Woodoats), discussed extensively. Several hosts are repeated from previous authors, one very likely in error: Sorghastrum sp. (Indiangrass), a host of A. alternata . The larva is illustrated. A single brood is noted, flying in April through June.

Lori Spencer (2014) describes the ventral side of hegon as having “grayish green shading”. Two broods are suggested: April-July.

Jeffrey Glassberg (2017) described the ventral side as “green-gray, sometimes pink/purple-gray.” Interestingly he notes: “females usually tan [below]”. Here, he describes the broods as “two broods, second is partial, Apr-May, July-Aug.”

James L. Monroe & David M. Wright (2017) described the ventral side with “extensive gray overscaling…slight greenish sheen when fresh.” The habitat is described as “woodland openings and edges, streamsides” and the host is given as Brachyelytrum erectum (Bearded Shorthusk) .

Craig Marks (2017) was first to publish a note of two ventral color forms: “I have found two “forms” … of the Pepper and Salt Roadside Skipper in LA.” Marks described the habitat as “heavily wooded loess hills with deep ravines” and also noted “there was a great deal of cane growing, both in the ravines and along the road.” Marks additionally noted: “These skippers were extremely abundant, both on the road basking and taking nectar at wild garlic.” Lastly, it was noted that one out of five seen that day were of the tan variety. The tan variant was illustrated for the first time.

Craig Marks (2018) further noted the two ventral color forms: “At Sicily Island Hills WMA, I would estimate that one out of five seen were tan colored dorsally [correctly: ventrally] rather than the typical slate gray.” A single brood is reported for Louisiana, in March and April.

Phillip G. deMaynadier, John Klymko, Ronald G. Butler, W. Herbert Wilson, Jr., and John V. Calhoun (2023) described the ventral side of hegon in Maine and the Canadian Maritime Provinces as: “brown with grayish-green scaling…becoming more dark brown with wear.” They note one annual generation from late-May to mid-July with a flight peak in mid-June, and that the host in that region is unknown.