Resapamea diluvius Crabo

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 : 97-100

Resapamea diluvius Crabo sp. n. Figs 9-11, 38, 50, 53

Type material.

Holotype Male. USA, Washington, Grant County: Potholes, 1110' [338 m.], 46.982°N, 119.451°W, 23.V.2001, L. G. & E. K. Crabo leg./ Database # CNC LEP 00094165. CNC. Paratypes 80 males, 25 females. USA. Oregon. Sherman County: Biggs, 1 VI 1960, S. G. Jewett (1 female); Biggs Junction, 28 IV 1959, S. G. Jewett (1 male). Washington. Adams County: Sand Hills near Washtucna, 9 mi. N. of Kahlotus, 46.78°N, 118.53°W, 445 m., 22.V.1999, L. G. Crabo leg., sand dunes (1 male, 1 female); Irrigation Exper. Sta. Basin unit [47.008°, -118.567°], 30.V.1963, E. C. Klostemeyer leg. (1 male); Franklin County: White Bluffs ferry, 46.675°N, 119.449°W, 25.IV.2002, Strenge/Zack leg. (1 male); Grant County: [same data as holotype] (30 males, 10 females); [same locality as holotype], 1095' [334 m], 1.VI.2002, Crabo & Troubridge leg. (9 males, 2 females); [same locality and date as previous], Barcodes of Life CNCLEP70179 (1 male); stable dunes S of Moses Lake, 21.V.1994, J. Troubridge leg. (1 male); Road C SE at The Potholes, [same coordinates as holotype], 19.V.2001, J. Troubridge leg. (32 males, 9 females); [same locality and date as previous], Barcodes of Life CNCLEP70181 (1 female); Potholes, 1095' [334 m.], 46.989°N, 119.425°W, 4.VI.2005, E. K. & L. G. Crabo leg. (1 male, 1 female); Vantage, 46°54'N, 119°56'W, 22.IV.1998, J. Troubridge leg. (2 males). CNC, CSUC, JHS, JTT, LGCC, OSAC, TMC, WSU.

Etymology.

The name is derived from the Latin diluvium meaning deluge or flood. The Columbia Basin where this moth occurs in Washington was scoured repeatedly by cataclysmic floods at the end of the Ice Age.

Diagnosis.

Resapamea diluvius is most likely to be confused with Resapemea passer ( Guenée) (Figs 12-14), a common and widespread moth in North America. Resapamea passer is found in the Pacific Northwest where it flies on both sides of the Cascade Mountains, including at the type locality of Resapamea diluvius . Resapamea diluvius is less variable than Resapamea passer , which comes in a range in colors and patterns that includes dark brown, reddish brown, dull light yellow brown, or a mixture of light- and dark-brown forms. Resapamea diluvius is dark hoary gray brown or red brown, grayer than Resapamea passer on both wings, with a more streaky pattern distal to the cell due to pale-gray veins. A few specimens of Resapamea passer have streaky distal forewings, but this is due to dark veins against a lighter ground (the veins of most Resapamea passer are dark gray under magnification but do not contrast with the ground color). Most specimens of Resapamea diluvius have the streaky pattern accentuated by black between the veins in the distal subterminal area and terminal area across the width of the wing. In Resapamea passer , black scaling on the distal wing is uncommon, and is usually limited to the area distal to the cell and in the fold. Finally, white or cream in the lateral reniform spot is typical in Resapamea diluvius , whereas pale scales in the spot are variable in Resapamea passer : absent, darker yellow or tan if limited to the lateral portion, or filling the entire spot. Habitat association with dunes and early flight period are also characteristic of Resapamea diluvius , whereas Resapamea passer is found in a variety of wetland and agricultural habitats and usually flies later in the summer with a peak during late June and July.

The male genitalia of Resapamea diluvius are similar to those of Resapamea passer (Fig. 39). The cucullus of the valve is more massive than that of Resapamea passer , especially relative to the width of the valve, and the anal margin is more rounded. In the vesicas, the diverticulum bearing a ridge of spines ( cock’s comb) on the ventral surface is positioned slightly closer to the base in Resapamea diluvius , is smaller in size, and has a less pronounced ridge of spines than in Resapamea passer .

The female genitalia of these species are also similar. The bursa copulatrix of Resapamea diluvius is rounder than that of Resapamea passer (Fig. 51), with the ratio of length to width approximately 1.5 in Resapamea diluvius and 1.75 in Resapamea passer .

Description.

Head - Antenna of male nearly filiform with a slight constriction at base of each segment, with dense ventral covering of short cilia. Antenna of female filiform with single cilia on each side of each segment. Scape light tan, with dorsal tuft of light-tipped brown to dark brown-gray scales. Eye round, smooth. Labial palp with lateral aspect of first two segments and entire short distal segment covered in short and flat gray-tan, gray-brown, and dark gray scales, elongating to a ventral fringe of brush-like dark gray-brown scales. Frons smooth, covered in narrow dark brown-gray scales. Top of head covered in relatively long and narrow light-tipped gray-tan to dark brown-gray scales. Thorax - Vestiture of collar, thorax, and tegula similar, a mixture of long, narrow, apically notched light-tipped dark gray-tan to gray-brown scales, appearing medium-dark to dark gray-brown with dusting of lighter scales on central tegulae. Legs even dark gray brown, with three rows of spiniform setae on basitarsus and four irregular rows on other tarsal segments. Wings - Forewing length: males 16-19 mm; females 15-18 mm. Forewing with a mixture of gray brown, gray tan, red brown, gray, and blackish-gray scales, ground color appearing medium-dark to dark gray brown or reddish-gray brown, usually slightly darker in cell and in medial area distal to reniform spot and often also posterior to cubital vein from base to postmedial line and in terminal area; costa anterior to radial vein hoarier gray; cubital vein and distal branches lighter gray-tan or gray, often with black suffusion between veins in medial area distal to reniform spot and across width of wing in distal subterminal and terminal areas. Basal and antemedial lines similar, gray, faint and incomplete, partially double filled with ground or a slightly lighter shade thereof; basal line evident as patches of gray scales on costa and near base of cubital line; antemedial line usually evident as a faint gray spot on costa and a strongly zigzag gray line posterior to cubital vein. Medial line gray to dark gray, diffuse, gently excurved, variable in prominence from absent, a faint shade on mid-wing, or complete. Postmedial line double with consistent medial black component and variable absent to faint-gray lateral component, filled with a light shade of ground color, drawn sharply basad to level of mid-reniform spot on costa, smoothly excurved around reniform spot with lateral apex on R5 or M1, then oblique and slightly concave toward base from near subterminal line to junction of basal two-thirds and distal third of posterior margin, very weakly toothed on veins except for a stronger tooth on 1A+2A. Subterminal line light gray tan, diffuse, slightly offset toward base near costa and undulating elsewhere, variable from a faint spot on costa to complete, preceded by aforementioned black scaling in distal subterminal area. Terminal line a series of black chevrons on veins. Orbicular and reniform spots completely or partially outlined in black; orbicular spot variably absent, faint, or prominent, a small to medium-sized oval filled with color of adjacent wing; reniform spot moderate sized, weakly to strongly kidney shaped, filled with white to cream laterally, less prominently inferiorly, and in a few specimens as an incomplete row of medial scales, ground color medially, and with a central dark-gray to black lunule that is strongest at posterior end. Claviform spot black, strongest anteriorly, narrow, small to moderate sized, filled with ground color or a darker gray shade thereof. Fringe ground color, usually with a lighter base and gray medial line. Dorsal hindwing slightly brownish gray, darker and grayer on distal half, with a gray ill-defined oval discal spot and thin terminal line. Hindwing fringe light gray brown with a gray medial line. Abdomen - dark brown gray. Male genitalia - Uncus cylindrical, evenly downcurved, distal portion tapering to a fine point. Tegumen with large penicillus lobes. Juxta shield shaped, 0.75 × as high as wide, with shallow V-shaped ventral margin. Valve S-shaped, 4.5 × as long as wide (measured at mid-portion), nearly even in width except for slight constriction at base of cucullus; with stout knob-like basal saccular process extending dorsolater ally from base and nearly reaching base of costa, medial margin of this process with triangular mesial projection at base and concave mid-section, apex rounded. Sacculus reaching to or slightly dorsal to costal margin and extending distally to mid-valve. Clasper a smooth ridge. Ampulla short, nearly spherical. Digitus a weak ridge, partially covered by medial edge of cucullus. Cucullus well developed with rounded apical and anal ends, 1.75 × as wide as mid-valve; mesial surface covered by fine setae; corona an irregular row of stout curved setae, partially double at anterior end. Aedeagus tubular, 4.5 × as long as wide, with a slightly elevated patch of minute spinules on ventral distal end. Vesica 0.67 × as long as aedeagus, bent 135° toward right at base to project anteriorly and toward right, basal half bulbous and distal half tubular, adorned with several diverticula and cornuti; a broad diverticulum on subbasal ventral surface with sclerotized apex with a cocks-comb row of short spines oriented along aedeagus axis and projecting ventrad; a membranous conical apical diverticulum on posterior vesica projecting anteriorly and rightward; a solitary cornutus on medial posterior surface comprised of a proximally-angled spine arising from a button-like base; and subapically, a patch of variable-sized spine-like cornuti directed proximally. Female genitalia - Ovipositor lobe elongate, dorsoventrally flattened and curved slightly ventrad at apex, 0.33 × as wide as long at base, narrowing near base to 0.25 × length, and tapering over distal third to a blunt point; proximal segments fused ventrally and dorsally to past mid-point; covered entirely but sparsely by long fine hair-like setae. Abdominal segment VIII 2 × as wide as long, anterior apophysis 1.25 × length of segment VIII and posterior apophysis 2.25 × length of segment VIII. Ostium bursae moderately sclerotized, ventral lip smoothly rounded and projecting posteriorly to cover ostium. Ductus bursae cylindrical, rugose, 1 × as long as segment VIII and 1.33 × as long as wide. Corpus bursae unisaccate, broadly ovoid, 1.50-1.56 × as long as wide, slightly asymmetrical with rounded projection on left extending slightly posterior to attachment of ductus bursae with ductus seminalis at apex.

Distribution and biology.

This species occurs in the Columbia Basin in Washington and northern Oregon. Specimens from dunes in northern Nevada and the northern Great Plains have been examined but the limits of its distribution are not well known.

The early stages of Resapamea diluvius are unknown. The larvae most likely feed on Rumex venosus Pursh ( Polygonaceae ) based on their close association with this plant in the Columbia Basin. This rue is abundant on the dunes where Resapamea diluvius occurs (Fig. 53) and the moth has not been found in Columbia Basin dune systems from which the plant is absent. Some other Resapamea species such as Resapamea passer are known to feed on Rumex species ( Tietz 1972).

Adults fly from late April to early June. No specimens have been found at the type locality during summer or fall, although Resapamea passer occurs there during the summer. Resapamea diluvius is local but is often abundant where it occurs.

Remarks.

The CO1 sequences of Resapamea diluvius and Resapamea passer are nearly uniform within each species but differ from each other by over 3.5%.

Hadena hulstii Grote, Hadena morna Strecker, and Hadena virguncula Smith are considered to be synonyms of Mamestra passer Guenée ( Lafontaine and Schmidt 2010). All were described from Colorado. The holotype of Hadena hulstii could not be located and is presumed lost (Lafontaine JD pers. comm. 2012). The holotypes of the other two were examined ( Hadena virguncula from a photograph) to exclude the possibility that they refer to Resapamea diluvius .