Drasteria parallela Crabo & Mustelin

Crabo, Lars G., Davis, Melanie, Hammond, Paul, Tomas Mustelin, & Jon Shepard,, 2013, Five new species and three new subspecies of Erebidae and Noctuidae (Insecta, Lepidoptera) from Northwestern North America, with notes on Chytolita Grote (Erebidae) and Hydraecia Guenee (Noctuidae), ZooKeys 264, pp. 85-123 : 90-94

Drasteria parallela Crabo & Mustelin sp. n. Figs 3, 33, 45

Type material.

Holotype male, USA, Washington, Chelan County: Chumstick Mtn, 47.63-.64°N, 120.44°W, 5100' [1554 m.], 21.VI.2004, L. G. & E. K. Crabo leg. CNC. Paratypes 22 males, 2 females. USA. Oregon. Jackson County: Siskiyou Mts., Mt. Jackson summit and S slope on Rt. 20, 42.07-.08°N,122.71-.72°W, 3.VIII.1995, Troubridge & Crabo leg., alpine and subalpine (1 male); Soda Mt. Rd., [42.065°, -122.478°], 28.VI.1986 (1 female); Klamath County: Keno, [1248 m.], 30.V.1939, S. Jewett, Jr. leg. (1 male); Lake County: Drake Pk., 6400' [1951 m.], 29.VI.2006, H. E. Rice leg. (1 male); Warner Mts., S slope & summit of Drake Peak, 42.29°N, 120.14-.15°W, 7860 –8220’ [2396-2505 m.], 2.VIII.1995, J. Troubridge & L. G. Crabo leg. (1 male). Washington. Chelan County: Chumstick Mtn, 47.63-.64°N, 120.44°W, 5100' [1554 m.], 21.VI.2004, L. G. & E. K. Crabo leg. (6 males); Derby Cyn., 47.60-.62°N 120.49-.55°W, 2130 –3130’ [649-954 m.], L. G. & E. K. Crabo leg. (1 male); Kittitas County, Quartz Mts., 47.074°N, 121.061°W, 1900 m., 7.VII.2005 (1 male); [same locality and collector], 14.VII.1990 (1 male); [same locality], 28.VII.2003, L. G. & E. K. Crabo leg. (1 male); Quartz Mtn., 6232' [1900 m.], 1.VII.1998, K. Romain leg. (1 male); [same locality and collector], 7.VII.1998 (1 male); 28.VII.1998 (1 male); Klickitat County: Simcoe Butte, 45.99°N, 120.66-.71°W, 3240 –4720’ [988-1439 m.], 7.VII.2000, L. G. & E. K. Crabo leg. (4 males); Yakima Co., Satus Cr., [46.217°, -120.433°], 28.V.1949, E. C. Johnston leg. (1 female); [same locality and collector], 29.V.1949 (1 male). CNC, LGCC, OSAC, TMC, WSU.

The type series is restricted to Oregon and Washington.

Etymology.

The name refers to the parallel lines across the pale medial area of the forewing of this species. This name perpetuates the geometry references of the related species Drasteria divergens (Behr) and Drasteria convergens Mustelin.

Diagnosis.

Drasteria parallela is most closely related to Drasteria convergens (Fig. 4), a species that occurs to the south of its range in California as far north as Mono County. Both have a medial line comprised of distinct parallel components, but the dorsal hindwing of Drasteria convergens is light red rather than orange. In the Pacific Northwest Drasteria parallela is most likely to be confused with Drasteria divergens (Fig. 5), which is similar in size and has a similarly colored orange hindwing. They can be distinguished without dissection by the pattern of the medial areas of both wings. The forewing medial line of Drasteria parallela is double with parallel component, whereas Drasteria divergens has a single broader medial line. On the hindwing, the discal spot of Drasteria parallela is nearly rectangular and the veins between it and the postmedial line are dark and contrasting. The discal spot of Drasteria divergens is joined broadly to the postmedial line giving it a long curved C-shape and the adjacent veins are orange. They also differ in other features of the maculation, including a smoother subterminal line in Drasteria parallela .

Structurally, the valves of Drasteria parallela and Drasteria convergens (Fig. 34) can be distinguished from those of Drasteria divergens by the nearly equal lengths of the two claspers and more rounded valvulae. In Drasteria divergens (Fig. 35) the right clasper is longer and more slender than the left and the posterodorsal valvulae are angular. Drasteria parallela has a relatively short and wide costal process of the right valve compared to that of Drasteria convergens in which it is long and narrow. In the vesica, the posteriorly-directed process arising from the glove-like diverticulum on the left side of the dorsal vesica is conical in Drasteria parallela and conical with two small finger-like projections in Drasteria convergens .

The female genitalia of Drasteria parallela and Drasteria convergens (Fig. 46) are told easily from those of Drasteria divergens (Fig. 47) by their much shorter antevaginal plates, which are rectangular and over half the length of the ductus bursae in Drasteria divergens , and by the presence of a narrow curved extensions of the pseudobursae that is absent in Drasteria divergens . The female genitalia of Drasteria parallela differ from those of Drasteria convergens by the size of the antrum of the ductus bursae, which is similar in length to the colliculus in Drasteria parallela , but twice as long in Drasteria convergens , and by the shape of the corpus bursae, which is rounded in Drasteria parallela , but ovoid in Drasteria convergens (ratio of width:length 0.87 and 0.7, respectively).

Description.

Head - Antenna of male filiform, densely ciliate ventrally with length of cilia approximately 1 × width of central shaft. Antenna of female filiform with single short cilia on sides of each segment. Scape covered in short tan scales. Eye round, smooth. Palpus covered in short gray-tan and scattered dark-gray scales, longer and lighter colored on ventral third. Frons smooth, it and top of head covered in long gray-tan scales. Thorax - Vestiture of long, narrow, apically notched, gray-tan and brown scales, forming vague tufts on posterior thorax. Prothoracic collar tan with longitudinal dark gray stripes at each side of head. Tegula covered in similar scales as thorax, with dark-brown medial and lateral stripes. Legs covered in gray-tan and scattered dark-gray scales; tibiae lacking spiniform setae; tarsal segments with three rows of spiniform setae. Wings - Forewing length: males 17-20 mm; females 18 mm (n=1). Forewing covered with brown, tan, and gray scales, ground color of wing base to antemedial line and subterminal areas dark brown with tan and lead-gray mottling, medial area light tan, darker near costa, and terminal area whitish gray to gray medially and blue gray to brown gray at margin, with a dark gray to black spot at apex; a complex mark resembling a large reniform spot in distal medial area between true reniform spot and strongly dentate postmedial line white medially and along dark crossing veins, tan laterally. Basal, antemedial, and postmedial lines similar, wide, partially double, black with chestnut-brown filling; basal line oblique from medial costa near wing base toward outer margin, fading at mid-wing; antemedial line complete, convex toward outer margin, drawn strongly toward wing base on costa, mid-wing, and posterior margin; postmedial line complex, costal origin near reniform spot, anterior portion strongly oblique toward outer margin to strong tooth on M1, slightly concave between M1 and M3, less strongly toothed on M3 and CuA1, then drawn strongly toward base and bending slightly anteriorly to posterior end of reniform spot, then bending sharply to meet posterior margin at a slight angle toward outer margin, portion posterior to reniform spot appearing to form a continuous line with medial margin of spot. Medial line dark gray, double,with nearly parallel components of equal strength across width of wing. Subterminal line double with dark brown to black inner and gray outer components, filled with tan, smooth with slight undulations, slightly offset toward base below the costa and convex toward outer margin elsewhere, preceded by a black line or series of black wedges or smudged marks between veins. Terminal line black, slightly scalloped. Orbicular and claviform spots absent. Reniform spot ovoid or weakly C-shaped with wider posterior end, black, open posteriorly, filled with dark brown, much less conspicuous than pale medial area lateral to it. Fringe slightly scalloped, dark gray brown with tan to brown base, weakly checkered in a few specimens. Dorsal hindwing ground color dull light yellow orange to dull orange, with strong suffusion of gray scales at base and along inner margin and gray on veins from base to postmedial line; discal spot black, nearly trapezoidal, with wider posterior end and concave lateral margin, posterior portion not reaching or barely touching postmedial line; postmedial line black, slightly wider than discal spot, irregularly zigzag with three angulations, lateral on M2, medial on CuA1 and CuA2, and lateral between CuA2 and inner margin; terminal line black, slightly thinner than postmedial line with inner border roughly parallel to outer edge of postmedial line. Hindwing fringe similar to hindwing ground color, but with variable gray suffusion on and adjacent to veins, strongest near Rs, M1, and M3-CuA2. Abdomen - covered with a mixture of gray-tan and dark-gray flat and tan hairlike-scales, appearing even medium-dark gray brown. Male genitalia - Uncus strongly curved, slightly compressed laterally, with a dorsal ridge on distal half, tapering to acute apex. Scaphium long and narrow with articulation at uncus base. Juxta H-shaped, 1.2 × as high as wide. Valves racquet shaped, asymmetrical, right longer and wider than left (width:length 0.34 versus 0.26, respectively), with slight posterior projection from dorsolateral left valvula and rounded dorsolateral right valvula. Sacculus 4 × as long as wide, extending distally to mid-valve; saccular extensions asymmetrical, stronger on right with distal long tooth-like process projecting dorsomedially and weaker one on left with distal small point; pulvinus moderately strong on both sides. Costal processes roughly triangular, asymmetrical, 4 × as large on right as on left. Claspers symmetrical in length, 0.25 × length of valve, cylindrical, distal portions slightly asymmetrical with stronger curve toward midline on left than right; base of clasper raised into small rod-like cone with patch of fine setae at apex on both sides. Aedeagus tubular, 4 × as long as wide, with membranous granulose patch at dorsal left apex extending onto adjacent vesica base and sclerotized narrow extension onto ventral left vesica base (ventral plate of carina). Vesica bulbous, approximately 1 × as long as aedeagus and 1.2 × as wide as long, larger on left, with complex anatomy of multiple diverticula; ventral diverticula from left to right: mid-left-lateral spherical with granulose surface, basilar-left-lateral triangular with pointed anterior projection and granulose surface, ventral-basilar ovoid with two short projections to left, and mid-right-lateral spherical with granulose surface; dorsal diverticula from left to right: distal-left-lateral glove-shaped with seven small radial projections and single larger posterior projection at base, dorsal-distal ovoid with posteriorly-directed apex, and distal-right-lateral glove-shaped with four finger-like projections. Female genitalia - Ovipositor strongly telescopic. Ovipositor lobe long and narrow, 5 × as long as wide, tapering to a rounded point, covered sparsely by long hair-like setae that are most dense at apex. Abdominal segment VIII slightly longer than wide, covered by hair-like setae that are most dense at posterior margin; anterior apophysis 1.25 × as long as segment VIII and posterior apophysis 1.8 × as long as segment VIII. Ostium bursae nearly as wide as segment VIII, membranous ventrally, with sclerotized, broadly V-shaped, lamina postvaginalis posterior to ostium. Ductus bursae 1.5 × as long as segment VIII, nearly straight except for slight rightward bend at anterior end; antrum at posterior end short, similar in width to ostium and 1 × as wide as long; lamella antevaginalis weak, 0.5 × as long as wide; strongly sclerotized tubular colliculum 1.8 × as long as wide, slightly longer on left side. Corpus bursae slightly asymetrically ovoid, nearly round, 1.15 × as long as wide, with small pseudobursa at right posterior end with narrow tubular extension from posterior end curving dorsad, anterior, and to right to project toward anterior right with ductus seminalis at tip.

Distribution and biology.

Drasteria parallela is found in the Cascade Mountains of Washington, the Klamath and Siskiyou Mountains of southwestern Oregon and northern California, and the northern Sierra Nevada in California. It is most commonly collected on exposed ridges in forests at middle elevations. It flies during July. The early stages and foodplant are unknown. Barcodes suggest a close relationship of Drasteria parallela and Drasteria convergens to Drasteria howlandii (Grote), which feeds on Eriogonum Michaux ( Polygonaceae ) ( Powell and Opler 2009).

Remarks.

This species has until now been called Drasteria convergens in the PNW.

The barcode of a single sample of this species from Plumas County, California (BOLDSYSTEMS Sample ID: CNCNoctuoidea7767) differs by 1.3% from that of Drasteria convergens from Mono County, California.