Aegiale occidentalis KC, McGuire & Shirey sp. nov.

Figs 1 a, c, 2, 3 a, 4 Suggested English name: Western Tequila Giant Skipper.

Material examined.

Holotype • ♀, Mexico: ‘ MEX: Son.: Rt. 16, [handwritten, black ink] 7 [/ handwritten, black ink] mi / E of jct Rt. 117 (San Nicolas) // [underside of first label; handwritten, black ink] 6 / 20 / 92 // MGCL collection / W. McGuire Coll. / Ex K. Roever // MGCL Unnumbered / Acc. – W. McGuire / ex. K. Roever // Genitalic Vial / KW- 24-135 / K. R. Willmott // [red label with black border] HOLOTYPE ♀ / Aegiale occidentalis / KC, McGuire & Shirey // [green barcode label] UF / FLMNH / MGCL 1199968 // DNA sample ID: / NVG- 24063 C 05 / c / o Nick V. Grishin’ in MGCL (Fig. 1 a, c).

Diagnosis.

Aegiale occidentalis sp. nov. can be distinguished from A. hesperiaris based on several morphological characters. 1) On the dorsal forewing, A. occidentalis sp. nov. exhibits dark orange apical spots whose inner margins are not aligned, with the basal edge of spots M 1 and M 2 not curving inward. In contrast, A. hesperiaris displays three white to whitish anterior apical spots whose inner margins are aligned or nearly so, with spots M 1 and M 2 pale orange and with their inner margins characteristically curved inward. 2) Spots CuA 1 and M 3 are obliquely inclined toward the costa in A. occidentalis sp. nov., whereas they are more vertical in A. hesperiaris. 3) The forewing discal cell spot in A. occidentalis sp. nov. is entirely orange whereas, in A. hesperiaris, the upper portion is white to whitish. 4) Ventrally, A. occidentalis sp. nov. is a darker gray, while A. hesperiaris is paler gray. 5) In dorsal view, the papillae anales in female genitalia are ~ 2 × longer than wide in A. occidentalis sp. nov., while they are> 3 × longer than wide in A. hesperiaris. 6) The sterigma is overall shorter with the lower margin unsclerotized and the upper margin with two round humps in A. occidentalis sp. nov., while it is longer with all margins well sclerotized and the upper margin concave in A. hesperiaris.

Description.

Female (Holotype). Dorsal (Fig. 1 a). Head. Narrower than thorax; 5 mm wide and 4.8 mm long; antennae mostly scaled white, some dark scales around clubs, 19 mm long extending beyond middle of forewing costa, with long, slender clubs and short 6 - segmented orange brown apiculi; eyes black; palpi short; scales salt-and-pepper dorsally. Thorax. 12.5 mm long and 10 mm wide; pronotum with dark gray scales; mesonotum laterally lighter gray and medially covered with long ochraceous / orange scales; metanotum mostly covered with ochraceous scales. Wings. Forewing 44 mm long; background blackish brown; base covered with long orange scales; orange area below discal cell extending from base to discal area and running along dorsum merging with discal band; discal orange band extending from space CuA 2 to discal cell spot, uniformly orange but lighter than basal orange patch; lower portion of spot CuA 2 longer than upper portion; spot CuA 2 (shorter) and CuA 1 (longer) offset forming an acute notch at inner margin; spots CuA 1 and M 3 (subequal) inwardly arrow-shaped, completely aligned; spot M 3 connected to discal cell spot forming an obtuse notch at distal margin; discal cell spot single without prominent cleft; subapical spots M 2 – R 3 unevenly conjoined; spots M 2 and M 1 (subequal) completely aligned; spot R 5 (shorter) approximately half aligned with spots M 1 and R 4; spots R 4 and R 3 aligned by more than half; spots M 2 – R 4 uniformly orange, spot R 3 somewhat paler, suffused with costal scales; costa covered with gray overscales; cilia checkered black and white. Hindwing length 35 mm; background color same as forewing; base to postdiscal area covered with long orange scales which merge with postdiscal band but continue along dorsum to submargin; orange oval discal cell spot obscured by long orange overscales; space 1 A + 2 A pale orange from base to near submargin; postdiscal orange band curved inward, extending from space CuA 2 to space Sc + R 1; spots of uneven length; spots M 2 and M 1 subequal and fully aligned; rest of discal spots shorter; spot Sc + R 1 as a faint patch; spots M 1 (long) and Rs (short) approximately half aligned with the band forming an obtuse notch outward; spots M 3 (short) and M 2 (long) approximately half aligned with the band forming a right-angle notch outward; cilia checkered black and white. Abdomen. 16 mm long and 10 mm wide; segment I-II fully covered in orange scales; segment III medially covered in orange scales; segment IV orange patch sparse; remaining areas covered in black and brownish scales; end of segments lined with brownish scales which become more profuse after segment V.

Ventral (Fig. 1 c). Head. Palpi white mixed with sparse dark gray scales; proboscis brown, 20 mm long. Thorax. Covered with long hair-like scales; prothorax with a dark gray band; rest of thorax with dark gray scales. Legs brown covered with similar gray scales; tuft of woolly hair-like scales on inner sides of femur and tibiae; femurs mostly brown; tibiae and tarsi with continuous series of strong brown spines on inner sides extending to a lateral side except for foretibia which only has an epiphysis; tarsi ending with bifid claws; pulvillus large, semicircular, pad-like; tarsal formula 5-5 - 5; tarsal spur formula 0-2 - 2; femur longest in midleg and shortest in hindleg; overall midleg longest, foreleg shortest. Wings. Forewing with blackish brown background; gray overscales run across costal margin, more pronounced and widened at apical portion and narrowed along termen; spots same as on dorsal side; discal spots M 3 and CuA 1 narrowly separated from each other and remaining spots by dark veins; apical spots more widely separated. Hindwing almost fully clothed in dark gray overscales except some black patches; dorsal spots reflected as gray muted spots black-banded on inner margins; two prominent black patches along costa at basal and discal portion; a strong pale orange bar runs along vein 1 A + 2 A to postdiscal region. Abdomen with mostly dark gray scales; smudges of black scales mostly along margins of V and VI segments; tip covered with gray scales; segment VIII concealed within and attached to sterigma.

Eggs (Fig. 2): Dome-shaped; 2.5 mm diameter, with ~ 0.6 mm circular depression on top; color amber in the museum specimen, potentially whitish in the field (the holotype was a gravid female whose eggs were observed during genitalia preparation).

Female genitalia (Fig. 3 a): Papillae anales almond-shaped, ~ 2 × longer than wide, with rows of long dense setae; sterigma sclerotized; fold below papillae anales (upper fold) with a broadly convex hump on either side separated by a median cleft; a sclerotized lower margin borders fold except at terminals; lower fold with a lateral lobe extending on each side that widens in middle; upper margin of inner fold with square corners, sclerotization diminishing toward center of margin; lower margin lined by broadly convex folds at sides connected to lateral folds; bottom of lower margin not lined by sclerotization; ostium ventrally opening; ductus and corpus bursae membranous with no visible signa.

Male. Unknown.

Distribution

(Fig. 4): Known only from the type locality in San Antonio, Sonora State, Mexico. The coordinates (28.415, - 109.110) are estimated from specimen label data and are not GPS-derived. The elevation of the type locality is estimated to be ~ 1170 m.

Flight.

June, potentially also in August (see Bailowitz et al. 2017 and discussion below).

Etymology.

The species epithet occidentalis is treated as a noun in apposition, derived from Latin occidentalis meaning ‘ western, ’ referring to the species’ known distribution in the Sierra Madre Occidental of western Mexico.

Deposition.

The holotype is deposited in the MGCL collection.

Holotype condition.

The holotype is in good condition except that the abdomen was removed for genitalia analysis, the proboscis was removed for measurement, and the hindlegs were removed for DNA sequencing. The genitalia and abdomen are preserved in a separate collection in glycerin and labeled with a unique number (KW- 24-135) corresponding to the specimen, while the proboscis and a bleached portion of the foreleg are pinned beneath the specimen in a capsule.

Remarks.

Based on the original descriptions and available images and illustrations of the type material for each name, we are confident that none of the species-level names currently associated with Aegiale hesperiaris apply to the species described here. In Aegiale kollari C. Felder & R. Felder, 1860 (original description: p. 111; table 2, fig. 3) and Teria agavis P. Blásquez & I. Blásquez, 1865 (original description: p. 21; Lam. 2 a), the white apical and costal spots diagnostic of A. hesperiaris are either clearly illustrated in the original figures or stated in the descriptions. Castnia hesperiaris Walker, 1856 was described without an accompanying illustration; however, Walker explicitly noted the presence of “ two irregular oblique pale testaceous subcostal streaks ” (original description: p. 1583), consistent with the pale costal markings characteristic of A. hesperiaris. We are confident that the image of the type specimen available on Butterflies of America (Warren et al. 2024) corresponds to one of Walker’s syntypes. None of these names corresponds to A. occidentalis sp. nov., which differs in having the apical and costal spots entirely orange, in addition to other diagnostic wing-pattern differences outlined in the Diagnosis and illustrated in Fig. 1.