Sympistis seth Troubridge, 2008

Troubridge, J. T., 2008, A generic realignment of the Oncocnemidini sensu Hodges (1983) (Lepidoptera: Noctuidae: Oncocnemidinae), with description of a new genus and 50 new species, Zootaxa 1903 (1), pp. 1-95 : 14-15

Sympistis seth Troubridge sp. n.

(Figs. C-4, K-11, P-10)

Diagnosis. Sympistis seth is quite similar to S. incubus but more closely related to S. duplex (Fig. C-3). Externally, S. seth is distinguished from S. incubus by the hindwing fringe, white in S. seth but with a thin brown medial line in S. incubus and S. duplex ; the basal area of the hindwing of S. seth is paler than that of S. incubus , and the forewing of S. incubus is darker with the ordinary lines and spots more narrowly demarcated and with darker scales: that of S. seth is more boldly patterned and with a paler ground color. Sympistis seth is most easily separated from S. duplex by range: S. seth occurs in xeric sand habitats throughout eastern Oregon and Nevada; S. duplex has been collected in southern California. The black dashes in the postmedial space of the forewing of S. duplex are usually bordered with white scales (absent except below vein CuA 1 in S. seth ), and the basal hindwing of S. duplex is darker (ie. more heavily suffused with dark scales) than that of S. seth .

Description. Males and females similar. Antennae filiform, head buff with a few white scales on vertex. Prothoracic collar white basally except at back of head, then lines of black, buff, brown, buff, brown, and buff. Thorax and abdomen a mix of buff, black, and white scales. Coremata with brushes, levers, and pockets absent from base of male abdomen. Forewing length 14-17 mm. Dorsal forewing ground color buff brown; buff denticulate antemedial line bordered distally with black and basally with brown scales; undulating postmedial line multicolored – from mesial band a series of dark brown, then light brown, black, buff, and finally light brown lines, these lines most distinct below reniform spot; black antemedial line deeply denticulate, edged basally with buff scales; basal line black; a weak series of black dashes extend between veins through postmedial area almost to black terminal line edged basally with cream scales; subterminal line occurs as a series of buff dots or chevrons within these black dashes; scattered white scales on veins basal to postmedial line; black scales on veins distal to postmedial line; white scales border veins CuA2 and 1A+2A distal to postmedial line; orbicular, reniform, and claviform spots well demarcated with black outer and off-white inner lines and an inner ring of brown scales; fringe a series of cream, brown, white, purplish brown, white, and finally buff lines. Dorsal hindwing off-white basally with wide, dark grayish brown marginal band; fringe cream basally, a thin, a very faint darker cream line, then white distally. Male genitalia. (Fig. K-11) Valve with rounded, upturned apex; ampulla of clasper talon-like, mid-section slightly widened. Vesica bends downward to the right and then straight downward; a ribbon of fine cornuti at base of vesica on dorsal surface extends ½ way along right side of vesica; vesica abruptly widens on left surface where a dense patch of long cornuti occurs on left surface along medial half of vesica; a ribbon of fine cornuti extends along terminal ½ of posterior margin of vesica; a single, coarse apical cornutus and small bundle of cornuti projected from apex. Female genitalia. (Fig. P-10) Ovipositor lobes rounded with scattered setae; a corona of short setae surrounds ovipositor lobes near tip, these setae produced at 90° to the abdomen, a ruff of longer, finer setae encircles ovi- positor lobes at base; a sclerite occurs on ventral surface of ductus bursae at ostium bursae, ductus bursae otherwise not heavily sclerotized; appendix bursae bulges evenly to left and right of ductus bursae, rounded at anterior end where ductus seminalis arises on dorsal side; corpus bursae absent.

Type material. Holotype male: USA: Oregon, Lake Co., Alkali Lk ., 43° 00' N, 120° 00' W, 4700’, 14 ix 1998, J. Troubridge, in the CNC . Paratypes: 51♂ 2♀: Oregon: same data as holotype , 17♂; Lake Co., Dunes 2 mi N Alkali Lk., 6 ix 1997, J. Troubridge , 2♀; Crook Co., Weberg Rd. , 1 mi N. Weberg, 5 ix 1997, J. Troubridge , 1♂; Malheur Co., 12 mi. SW Vale , 43° 52' N, 117° 21' W, 2670’, 22 ix 2001, J. Troubridge , 13♂; Malheur Co., 12 mi. SW Vale , 43° 52' N, 117° 21' W, 2670’, 21 ix 2002, J. Troubridge , 15♂; Malheur Co., Sand Hollow , 43° 48' N, 117° 22' W, 2500’, 27 ix 1998, J. Troubridge , 1♂. Nevada: Humboldt Co., Winnemucca Mtn. , 41° 01' N, 117° 46' W, 5600’, 20 ix 2001, J. Troubridge , 3♂.

Etymology. Seth is the Egyptian god of chaos, the embodiment of hostility and evil. It is a noun in apposition.

Distribution. This species is known from dune habitats in eastern Oregon and Nevada.