Diagnosis.
Adults. Males and females similar in size and habitus, medium-sized (forewing length 17–21 mm) long-winged, stout noctuid moths; distinguished by combination of densely hairy eyes and gray forewing with a whitish, light tan, and reddish brown flame-like mark in both shape and colorfrom the medial reniform stigma to the jagged subterminal line. Head – Male antenna beaded weakly with slight constriction between segments, anterior, posterior, and ventral sides setose with innumerable short fine cilia; female antenna simple with few short lateral cilia. Scape whitish to gray tan, with ventral acute tuft. Eye normal size, densely setose. Labial palpus porrect, third segment length ~ ⅓ × second segment. Haustellum normal. Frons rounded, scales short, hair-like, forked, tan, brown, or gray brown. Dorsal head scales longer, forked, tan, gray, orange tan, sculpted weakly with paramedian dorsal and ventral protuberances. Thorax – Scales long, hair-like, forked, and scattered trifurcate, light tan, orange tan, and chestnut brown; appearing golden tan, with sculpted broad pale median tufts on mesothorax and metathorax and red-brown paramedian tufts on metathorax; prothoracic collar similar; appearing golden tan with pale-edged red-brown posterior band; tegula scales mostly white-tipped gray, forked; appearing gray with tan to red-brown medial edge. Legs: Lateral foretibia with row of 4–6 long, stout, slightly recurved, claw-like setae, proximal and distal longest; mid- and hindlegs lacking modified setae. Tarsal segments except apical segment with three rows of ventral spiniform setae. Wings: Forewing: Length 2.3–2.5 × width; apex pointed bluntly, outer margin slightly to moderately scalloped between veins; dorsal scales flat, fine toothed, elongate to triangular, white, gray, tan, and chestnut brown; ground color gray, darkest at costa and in cell, lightest at base; basal area posterior to vein 1A+2A light tan with anterior chestnut border; medial area distal to reniform spot and postmedial area whitish tan to tan, palest medially, forming with subterminal line and preceding chestnut shade a “flame” mark on distal ⅓ of wing; basal and antemedial lines double, gray with slightly lighter filling, undulating, perpendicular to wing axis; medial line dark gray, faint, diffuse; postmedial line thin, gray, faint, usually incomplete, scalloped strongly with points extended as thin dark lines and spots on veins, strongly oblique to wing axis from costa to posterior reniform stigma, less strongly to posterior margin; subterminal line thin, white to tan, bordered medially by prominent chestnut-brown and dark brown to black shade, darkest in fold, next darkest opposite reniform stigma, toothed to outer margin at apex and on M1, M3, CuA1, and 1A+2A, concave basad in fold; terminal line thin, black; fringe gray, striped, base pale tan or brown, pale transverse checkering at veins; claviform stigma dark gray to black, incomplete, apex darkest, short and broad, reaching mid-medial area, filling light gray; orbicular stigma black or chestnut brown, relatively large, ovoid to weakly figure-eight-shaped, filled variably with light gray, darker gray, light tan, and brown; reniform stigma moderately large, kidney shaped, usually with absent posterior and distal outline but evident due to whitish filling that contributes to palest portion of “flame” mark. Hindwing: Margin between M1 and M3 straight or concave; ground color pure white or slightly mottled light tan to brownish gray; veins, discal spot, and terminal line light to dark gray; fringe white to light gray with darker stripes, paler than ground. Abdomen. Male with or without basal coremata on segment I and pockets on ventrolateral segment III; when present weak, comprised of few filaments attached directly to base with pockets shallow, or strong, paint brush-like, filaments arising from rod with bulblike base, sometimes with very small medial accessory brushes, with pockets deep. Dorsal tufts on segments I–III. Female sternite VII sclerotized on distal half, with posterior median cleft 0.33–0.58 × segment length, blunt posterolateral lobes on side of cleft cover ostium bursae and part of ventral segment VIII. Male genitalia: Uncus relatively short, curved ventrad, base cylindrical, distal half widened and flattened dorso-ventrally, slightly concave dorsally with flange-like raised edges, tapering to truncate apex with small ventral spine; dorsal edges and ventral apex with numerous short setae. Juxta broadly shield shaped, wider than tall, smooth (A. similaris) or with median thorn-like spine directed posterodorsad (2 species). Valve length ~ 5 × width, S-shaped with slight curve dorsad near mid-point and 90° lateral bend distal to clasper at ⅔ distance from base to apex, tapered evenly from broad base to end of clasper, narrowing abruptly at bend to thin neck of cucullus, ventral margin of mid valve thickened with short blunt lateral projection ventral to distal clasper; sacculus length 0.4–0.5 × valve, sclerotized strongly, extending to or slightly above dorsal valve, distal costal margin near dorsal attachment of valve humped dorsad or anvil shaped, covered densely with minute setae; clasper strongly sclerotized, a bowl-like concavity dorsal and distal to sacculus, distal margin a narrow flange-like rim extended to blunt triangular dorsal and broad convex ventral projections, dorsal projection longer than (two species) or similar (one species) to ventral projection; digitus absent; cucullus triangular, 0.6–1.0 × mid-valve width, with slightly rounded margin bearing simple corona of 15–25 claw-like setae. Phallus tubular, length 6–7 × width. Vesica length (including right and left limbs) 1.0–1.5 × phallus, bent slightly ventrad at base then divided into nearly equal limbs directed 90° right and left to form with phallus a “T;” right limb comprised of distal vesica, tapered to ductus ejaculatorius at apex, with subapical broad short ventral diverticulum; left limb variable between species, tapering to conical or thin apical cornutus, bearing an additional thin acute cornutus at dorsal base (absent or diminutive in some specimens of all species) and anteriorly-directed broad conical subapical diverticulum (lacking in A. icarus). Female genitalia: Papilla analis asymmetrically conical, apex near dorsum, length 1–1.5 × width, covered sparsely on base and mid-portion by thin hair-like setae, more densely on apex by short setae. Abdominal segment VIII slightly longer than wide, venter length 2 × dorsum, covered sparsely by short hair-like setae; anterior apophyses length 0.57–0.77 × abdominal segment VIII; posterior apophyses length 2.75–3.35 × anterior apophyses. Ductus bursae length 1.14–1.32 × abdominal segment VIII, strongly sclerotized, flattened dorsoventrally, length ~ 3 × width, ventral surface smooth, dorsum rugose; ostium bursae simple. Corpus bursae length 3.9–4.6 × abdominal segment VIII, elongate, gourd shaped, anterior portion curved dorsad and leftward, membranous ovate anterior end widest, width 0.35–0.43 × bursa length, 3–4 longitudinal irregular string-of-beads signa evenly spaced on surface (left lateral signum absent in two species); appendix bursae projected ventrad and leftward from broad origin at junction with posterior corpus bursae at ductus bursae, length 0.12–0.25 × total corpus bursae length, sclerotized lightly, apex blunt, ductus seminalis at dorsum anterior to apex.
Discussion.
Admetovis was historically classified in the subfamily Hadeninae, where it was placed since the early twentieth century (Hampson 1905, McDunnough 1938, Hodges et al. 1982). It was reassigned recently to the tribe Noctuinae: Orthosiini (Lafontaine and Schmidt 2010) stemming from changes in the composition of the Noctuidae (Fibiger and Lafontaine 2005). Although the higher classification, including the recognition of Orthosiini as a tribe, is fairly recent (Fibiger and Lafontaine 2005) the relationship of Admetovis to other genera in this tribe is not obvious and had not been recognized widely. More recent molecular approaches to noctuid classification based on mtDNA barcode sequence data (Zahiri et al. 2017) support the current classification of North American Orthosiini in that nearly all included genera cluster together, but with the exception of Admetovis – this genus instead groups with genera in the Hadenini, which Godfrey also indicated as being the most closely related group to the orthosiine genera. This warrants a re-examination of Godfrey’s (1972) interpretation of larval hypopharynx structure, which forms the basis of the Orthosiini as currently defined.
Godfrey (1972) included nine genera in the Orthosia group (“Group 8”), noting that two other genus-groups were likely closely related based on the morphology of the hypopharynx, namely the spining pattern and especially the transverse cleft, the latter shared across the three groups. Godfrey’s three “transverse-cleft” groups comprise the Anarta-group, Polia-group and Orthosia-group, the first two now combined in the tribe Hadenini and the third comprising the Orthosiini. Although Godfrey separated the Orthosiini and Hadenini morphologically by two characters (lack of setae above the spinneret and larger spines on the proximolateral hypopharynx in Orthosiini), exceptions occur in both tribes (Godfrey 1972). Admetovis differs in the shape of the spinneret and the finely granular (vs. smooth) larval integument from all other Orthosiini, but these characters appear to be autapomorphic because they also do not occur in the Hadenini.
Importantly, Admetovis is the sole constituent of Godfrey’s Group 8 where adults do not emerge in early spring. Most species in the Orthosiini emerge very early in the season, and some, such as Orthosia praeses (Grote) and Egira hiemalis (Grote), are the first non-overwintering moths to fly in late winter. While A. similaris can be found as early as February in the deserts of the Southwest, most Admetovis differ from other orthosiines in that they fly later in the year from late spring through summer.
Finally, the male valves of Admetovis, S-shaped with triangular cuculli, are more similar to those of most hadenine moths (e.g., as shown for European species in Hacker et al. 2002) than they are to orthosiines (shown similarly in Ronkay et al. 2001), as are the everted vesicae. Females of both tribes are rather simple in genital structure and as a result are not highly diagnostic.
The weight of evidence (barcodes, biology, and adult genitalia structure versus somewhat equivocal larva hypopharyngeal structure) suggests that Admetovis is better classified in the Hadenini rather than the Orthosiini. A definitive phylogeny of the Noctuinae tribes, using multiple molecular and morphological markers, is still needed. As such, we recommend Admetovis as a fertile subject for further investigation.