Enargia infumata ( Grote, 1874 )

Schmidt, Christian, 2010, Review of the Nearctic species of Enargia Hubner, [1821] (Noctuidae, Noctuinae, Xylenini), ZooKeys 39 (39), pp. 205-223 : 208-215

Enargia infumata ( Grote, 1874)

Figs 1–18, 55, 59, 64.

Orthosia infumata Grote, 1874 ; 160.

Cosmia punctirena Smith, 1900 ; 222, pl. 5, f. 6.

Cosmia punctirena ; Dod 1905.

Enargia mephisto Franclemont, 1939 ; 115, f. 2, syn. n.

Enargia infumata ; Forbes 1954, in part

Enargia mephisto ; Rings et al. 1992, pl. XV f. 23. Handfield 1999, p. 92, f. 9551-1, 9551-2.

Type material. Orthosia infumata : lectotype female, here designated. BMNH, examined. Type locality: “Chautauqua Co., N. Y.” Although Grote’s (1874) statement in the original description that “specimens received from Mr. Geo. Norman” suggests that E. infumata could have been based on several syntypes, only one wing expanse measurement is given, and the type locality is restricted to Chautauqua Co., NY. Norman’s material originates from Ontario (M. Honey, pers. comm.). Th e type material most likely was a single Chautauqua Co. specimen, although this is not beyond question. To ensure the stability of the name Orthosia infumata , the following female specimen is therefore designated as lectotype: “Grote Coll.”; “ U.S. America / [crossed out, undecipherable] Co. / Chautauqua / Co. / N.Y.”; “1938. / 265”; “Type” [round, red bordered label]; Orthosia / infumata / Type Grote” [ BMNH]. Th e following label will be added: “ Orthosia / infumata Grote / Lectotype by / Schmidt, 2010”. Although the abdomen is missing, the specimen is otherwise in good condition, and shows the dusky grey-ochre forewing colour (probably reflected by the name infumata ) with a poorly contrasting reniform and orbicular, less sinuate AM line, dull ochre hindwing, and smaller wing expanse compared to the species previously thought to be E. infumata and described here as E. fausta .

Cosmia punctirena : lectotype male (designated by Todd 1982). USNM, photograph examined.Type locality: “Yellowstone Park, Wyoming.” Th e specimen illustrated by Smith (1900) is the lectotype designated by Todd (1982), and the relatively unicolourous, dark forewing, non-contrasting reniform and orbicular, and pronounced black spot in the reniform, show that E. punctirena is correctly attributed to the synonymy of E. infumata . Additional Barnes specimens collected in August in Yellowstone ( CNC) are of the same provenance as the original types, although these are not paralectotypes, and are also E. infumata . Th e original description of E. punctirena was probably based on a mixed series of E. infumata and E. decolor , as E. decolor specimens in the CNC from Glenwood Springs, Colorado (Barnes, September) and E. decolor from Cartwright, MB (Heath, August) are of the same provenance as the original syntype series. Although this does not affect the synonymy of punctirena , the diagnosis of the taxon by Smith is inaccurate.

Enargia mephisto : holotype male. CUIC, examined. Type locality: “Ithaca, New York.” see ‘Remarks’ below.

Diagnosis. Enargia infumata is most similar to E. fausta . Overall, E. infumata has a paler ochre, less yellow look to it with less contrasting markings and greater variation in colour. Th e unicolorous smoky-grey forms are unique to E. infumata (it was this phenotype that formed the basis of Franclemont’s description of E. mephisto ). Compared to E. fausta , E. infumata is slightly smaller, has slightly thicker, less sharply defined AM and PM lines (when these are visible at all), less sinuate PM line, a dull, pale ochre (vs. yellow-ochre) hindwing ground colour, and the reniform and orbicular are often concolourous with the forewing ground colour (not paler and contrasting), and with a discontinuous or absent outline (thin, crisp outline in E. fausta ). Specimens of E. infumata from the Prairie Provinces average slightly larger and paler than eastern E. infumata , and therefore have a general appearance more like that of E. fausta . Internally, the valve length is shorter in E. infumata (2.6–2.9 mm from apex to clasper at dorsal margin, vs. 3.3–3.5 mm in E. fausta ), the cornuti of the vesica are smaller overall (length of free apex less than 0.10 mm vs. greater than 0.11 mm in E. fausta ), with a relatively much larger sclerotized plate of the right cornutus (length of plate 4–5 × greater than length of free apex of cornutus, compared to 2.0–2.5 × in E. fausta ). Th e peniculum (tegumen lobes) are on average shorter and broader ( Franclemont 1939; Forbes 1954), but there is much overlap in shape between the two species and this is not a reliable diagnostic trait. In the female, the corpus bursae differs in size and shape, being longer (5–6 × length of segment VIII vs. 3.5–4.0 × in E. fausta ), and more narrow-elongate than E. fausta (Fig. 64).

Figures Ι–Ι8. Enargia infumata adults. Ι–3 ♁, Kootenay Plains, AB, CAN 4–ΙΙ ♁, Edmunston, NB, CAN Ι2 ♁, Taber, AB, CAN Ι 3 ♀, Panguitch, UT, USA Ι4–Ι 5 ♀, Kootenay Plains, AB, CAN Ι6–Ι 8 ♀, Edmunston, NB, CAN.

Redescription. Head – Antenna of male prismatic, segments as wide as long; antenna of female filiform and ciliate; scales of dorsal antenna, scape, vertex, and palpus unicolorous but co-varying with ground colour of wings, from pale ochre, yellow ochre, brownish grey, to dull rusty brown. Thorax – Vestiture of thorax, patagia and prothoracic collar unicolorous, but varying from pale ochre, yellow ochre, brownish grey, to dull rusty brown; legs dull ochre yellow with longer scales of corresponding colour on femur and tibia. Wings – Forewing length: eastern populations average slightly smaller at 16.4 mm (n = 6) versus 17.4 mm (n = 6) for western populations; females slightly larger overall at 17.5 mm (n = 3) for eastern and 18.4 mm (n = 3) for western

Figures Ι9–34. Enargia adults. Ι9 E. fausta , holotype ♁, St.-Basile, NB, CAN 20 E. fausta , ♁, Edmunston, NB, CAN 2Ι E. fausta , ♁, Temiscouata Co., QC, CAN 22 E. fausta , ♁, Black Sturgeon L., ON, CAN 23 E. fausta , ♁, Edmunston, NB, CAN 24 E. fausta , ♁, Peers, AB, CAN 25 E. fausta , ♁, Edmunston, NB, CAN 26 E. fausta , ♁, Black Sturgeon L., ON, CAN 27 E. fausta , ♀ St.-Basile, NB, CAN 28–30 E. fausta , ♀, St.-Basile, NB, CAN 3Ι E.? paleacea, Delta , BC, CAN 32 E. paleacea , ♁, Hungary 33 E. paleacea , ♀, Hungary 34 E. paleacea , ♁, Finland.

specimens; forewing ground color varying from pale ochre, yellowish ochre, brownish grey to rusty brown; dark markings varying from charcoal grey to reddish brown, and highly contrasting to virtually absent; angle of antemedial line rounded and obtuse, about 130°–140°; postmedial line evenly rounded to slightly sinuate; medial band varying from thick and diffuse to obsolete, co-varying with dark terminal and sub- apical shading; pale subterminal line present in specimens with dark terminal shading (Fig. 12); reniform and orbicular usually concolorous with wing ground colour or only slightly paler, rarely contrastingly pale; border of reniform and orbicular weakly defined and usually interrupted, or absent altogether; base of reniform (towards anal margin) with dark grey spot of varying size, but spot nearly always darkest of forewing markings; claviform absent; fringe concolorous with ground colour; ventral forewing less variable than dorsum, ground colour pale yellowish ochre with postmedial line and reniform spot variously developed, more so in specimens with contrasting dorsal markings and antemedial line absent. Hindwing ground colour pale yellowish ochre with dark shading varying in extent and colour from grey to dull maroon; postmedial line and broader, diffuse subterminal band visible when dark markings developed, varying to entirely absent; medial line better defined ventrally, with ventral discal spot similarly dark (rarely visible dorsally). Abdomen – Vestiture mix of pale yellowish-ochre and darker scales of colour of those on forewing dark markings; males with terminal and lateral scale tufts, which are absent in females. Male genitalia – (Figs 55, 59). Uncus cylindrical, tapering to a small distal hook; tegumen with large peniculum, consisting of long, triangular subdorsal lobe, 0.3 × length of valve, and short, rounded lobe adjacent to uncus base; valve 2.6–2.9 mm long, 4 × as long as wide (measured at widest part), corona extending from apex along ventral margin over 1/2 length of valve; sacculus 0.5 × valve length; clasper spatulate, recurved, and directed caudally; aedeagus 7 × as long as wide, tube shaped, with field of 10–18 short, stout backward-directed spines at ventral margin of apex; ventral margin of apex rounded and slightly scoop-like; vesica small, simple, bulbous, 0.4 × length of aedeagus, with two stout cornuti positioned laterally and directed caudad; free apex of cornuti equally sized (0.082 –0.099 mm); distal opening of vesica extending dorsally from vesica as gradually tapering tube. Female genitalia – (Fig. 64). Ovipositor lobes bluntly triangular in lateral view, ventral margin slightly concave, covered in short hair-like setae; abdominal segment VIII 0.7 × as long as wide, anterior apophysis 1.5 × and posterior apophysis 2.3 × length of abdominal segment VIII; ductus bursae extremely short, 2 × length of ostium, appearing thicker and more rugose than corpus bursae; long, duct-like proximal two-thirds of corpus bursae (which initially appears to be ductus bursae) with only slight widening toward ovoid distal chamber; corpus bursae 5–6 × length of segment VIII, lacking signa; ductus seminalis originating dorsad and slightly caudad of distal end of ductus bursae.

Distribution and biology. Enargia infumata has a broad North American distribution, occurring from Alaska south to California and the Pinaleno Mountains of Arizona, east to New Brunswick and New York. No specimens were seen from Nova Scotia although the species undoubtedly occurs there; the Nova Scotia specimen illustrated by Ferguson (1954: pl. x, fig. 4) is E. fausta . In the eastern part of the range, the peak flight period occurs between mid- and late July, with extreme dates from mid- June to mid-August. Enargia infumata flies three to four weeks earlier than E. fausta , and there is very little temporal overlap between the two in any given year; generally, E. fausta does not appear until late July and peaks in mid- to late August. Flight times for the boreal forest region from northern Ontario westward indicate slightly later

Figures 35–54. Enargia adults. 35 E. decolor , ♁, Temiscouata Co., QC, CAN 36 E. decolor , ♁, Princeton, BC, CAN 37–38 E. decolor , ♁, St.-Basile, NB, CAN 39–4Ι E. decolor , ♁, Edmunston, NB, CAN 42 E. decolor , ♁, Wainwright sand dunes, AB, CAN 43 E. decolor , ♀, Josephine, OR, USA 44 E. decolor , ♀, Hanwell, NB, CAN 45–48 E. decolor , ♀, Edmunston NB, CAN 49 E. decolor , ♁, Dalton Springs cmpgd., San Juan Co., UT, USA 50 E. decolor , ♁, Dalton Springs cmpgd., San Juan Co., UT, USA 5Ι E. decolor , ♀, Chiloquin, OR, USA 52 E. decolor , ♁, McGill, NV, USA 53 E. decolor , ♁, Durango, CO, USA 54 E. decolor , ♁, Mt. Graham, Graham, Co., USA.

flight dates for E. infumata: In central Alberta, E. infumata peaks from late July to mid August, with E. fausta again slightly later in mid- to late August.

McGuffin (1958) illustrates the larval head capsule and provides a detailed description identified as E. infumata , but given the past confusion of E. infumata and E. fausta , it is not certain which species his account pertains to. I have not been able to find vouchers or associated adults in McGuffi n’s material at the CNC. Prentice (1962) reports most larval collections (45/61) from Populus tremuloides Michx. , some from Betula papyrifera Marsh. (13/61) and a few collections from Salix sp. (2 collections) and Populus balsamifera L. (1 collection), but again it is not clear if these records pertain to E. infumata or E. fausta , but likely both, since E. mephisto is not mentioned in Prentice (1962). I have confirmed P. tremuloides as a definite (and probably preferred) host from reared specimens. Th e larval biology and description needs to be re-evaluated.

Remarks. Franclemont (1939) correctly recognized that three species were going un- der what had previously been treated as a single species, E. decolor . Dod (1905) also recognized early on that E. decolor and E. infumata were separate species, and gave several diagnostic traits separating the two (which I had initially overlooked, and Franclemont (1939) made no mention of either). Franclemont (1939) recognized a third species and described it as E. mephisto , based on two specimens. Comparison of phenotype and genitalic variation in long series of E. mephisto and E. infumata (of authors), and CO1 sequence data shows that these two taxa have been largely misunderstood. Variation in the size and shape of the tegumen arms (‘shoulders’ of Franclemont) shows that these characters are not diagnostic, and the most consistent male genitalic character is the size and position of the cornuti of the inflated vesica (Fig. 59) (Franclemont used uninflated vesicae in his diagnosis). Additional distinguishing characters are given under ‘Diagnosis,’ above.

Why Franclemont considered all of the other 81 specimens from sites across the continent to be E. infumata (of authors; = fausta ) rather than E. mephisto is not clear, since many western specimens are indistinguishable from eastern E. mephisto (compare Figs 1, 13, 16). Presumably he had few western specimens and lacked the ‘typical’ E. mephisto phenotype in his material, compounded by the slightly larger, paler western phenotype of E. infumata (Grote) , which therefore bears greater resemblance to E. fausta . It would therefore have been diffi cult to ‘draw the line’ between E. fausta and phenotypic variation in E. mephisto without long series of specimens and extensive comparison of dissections.

Following Franclemont’s revision, the more northerly pale species described herein as E. fausta and the paler forms of the widespread species E. infumata were both treated as E. infumata , whereas the darker forms of E. infumata were treated as E. mephisto . Enargia infumata (as E. mephisto ) was thought to be the less common taxon with a more easterly distribution ( Forbes 1954). In reality Enargia infumata s.s. is widespread and common, whereas E. fausta has a more restricted distribution.

The seventeen sequenced specimens of E. infumata from British Columbia, Alberta, Ontario, and New Brunswick exhibited seven haplotypes, differing at most by approximately 0.6 % from each other, compared to a 1.7% divergence from the single E. fausta specimen.

Figures 55–57. Male genitalia of Enargia . 55 E. infumata 56 E. fausta 57 E. decolor .