Ethmia scylla Powell 1973

Ethmia scylla Powell, 1971:12

A small, grayish brown moth somewhat resembling a pale E. brevistriga Clarke.

MALE.–Length of forewing 5.8 to 7.2 mm. Head: Labial palpus very short, nearly porrect, second segment length about 0.7 eye diameter; pale brownish exteriorly, whitish at base and interiorly; third segment subequal in length to second; scaling pale brownish, tip white. Antenna shaft moderately dilated (scarcely larger than in female), width of shaft near base about 0.3 eye diameter; densely setate ventrally, scaling dark brown. Scaling of vertex short, erect, roughened in appearance, becoming smooth below crown and on front; dark brown, some whitish scales at lower margins of front and on occipital margin. Thorax: Dorsal and ventral scaling pale brownish gray with intermixed white scales; tegula paler; metathoracic leg paler, with well-developed dorsal tibial fringe. Forewing: Length about 3.6 times width; termen strongly angled back to dorsum; fringe not as broad, relative to wing length, as in brevistriga so that wing not so truncate appearing. Ground color pale grayish brown; clouded and marked by whitish scaling as follows: a rather distinct, broad band along median fold to middle of cell, with distinct, dark indentations on its dorsal side at about its middle and distal end; a distinct white spot at end of cell margined by darker scales; a diffuse blotch on tornus extending up to spot at end of cell; a diffuse whitish area at apex, ending abruptly at midtermen. In well-marked specimens a distinct, curving bar of ground color runs from middorsum through end of cell to termen above tornus, interrupted only by and emphasizing the distinct white spot at end of cell. In some specimens (apparently not always worn) the white scaling is partially to almost entirely lost, leaving the spot at the end of the cell as a solitary marking. Fringe whitish except where curving brown bar meets termen, termen entirely whitish on unmarked specimens, or entirely brownish white. Underside pale brown, the spot at end of cell indistinctly reproduced, whitish along dorsum, a white spot at midtermen in fringe. Hindwing: Slightly narrower than forewing; costa sloping gradually to the acute apex, costal brush reduced to a dozen or so ochreous hairs. Ground color gray-brown; fringe whitish with basal brown band. Underside whitish, irregularly blotched with brownish. Abdomen: Dorsal scaling black, appressed, velvet-like on first two segments; interspersed brownish and whitish, with roughened appearance beyond. Ventral and genital scaling mostly whitish. Genitalia as in Figure 52 (drawn from paratopotype, JAP prep. no. 1466; three preparations examined); uncus broad, hoodlike, only shallowly notched; gnathos with a few blunt teeth posteriorly, with numerous elongate, curved teeth anteriorly; basal processes short, broad.

FEMALE.–Length of forewing 6.0 to 7.2 mm. Essentially as described for male. Forewing tending to be more heavily overlaid with whitish, the brown areas more well defined. Costal brush of hindwing lacking. Genitalia similar to E. coquillettella, the papillae anales not strongly sclerotized; sterigma a shallow funnel subtended by a row of small, weak teeth; ductus with 3 loops; signum broad, not flanged, the fold bearing a row of flat, blunt teeth (3 preparations examined).

TYPES.–Holotype male and allotype female: California, Russelmann Park (north slope of Mount Diablo, 1,100 feet), Contra Costa County, April 2, 1960 (J. Powell) deposited in the California Academy of Sciences. Thirty-six paratypes, all California, as follows: Russelmann Park, 1♂, III–18–59 (J. Powell), 14♂, 4♀, IV–2–60 (J. M. Burns and J. Powell), 9♂, 1♀, IV–6–62 (J. Powell); 3 mi NW Rumsey, Yolo County, 3♂, III–8–64 (J. Powell). Del Puerto Canyon, 20 mi E Patterson, Stanislaus County, l♂, II–23–63 (R. L. Langston), 6♂, III–5–63 (J. Powell). Deposited in collections of American Museum of Natural History, California Academy of Sciences, British Museum, California Insect Survey, R. L. Langston, and U.S. National Museum.

Subsequent to the above writing, Ethmia scylla adults were encountered in large numbers, and the biology studied, at the Del Puerto Canyon locality (Powell, 1971).

FLIGHT PERIOD.–Late February to early April.

FOOD PLANT.–Collinsia heterophylla (Scrophulariaceae); the larvae feed in the flowers. The pupa lacks the “anal legs” (Figure 290), presumably a secondary reduction.

Ethmia brevistriga Clarke

Ethmia brevistriga Clarke, 1950:163.–Powell, 1959:134;1962:67 [biol.]; 1971:17 [biol.].

A small, dark moth having the brownish gray forewing mottled with whitish. The typical subspecies, which has more extensive whitish markings, occurs along the immediate coastal strand in central California.

Ethmia brevistriga brevistriga Clarke, new status

MALE.–Length of forewing 5.6 to 6.4 mm. Head: Labial palpus short, little upcurved, second segment slightly shorter than eye diameter, only slightly curved, rough scaled whitish below, smooth scaled dark brown above; third segment subequal in length to second, relatively broad and blunt, dark brown with a few scattered white scales. Antenna dilated, shaft diameter near base about one-third eye diameter, setation reduced, dark brown with scattered pale scales. Scaling of front smooth, of crown rather rough, of occipital margin spreading, brownish black with scattered whitish scales, paler along lower margin of front and base of proboscis; a broad white scale tuft below palpus; an unsealed, shining black plate behind eye. Thorax: Dorsal scaling brownish black, tegula whitish distally. Underside shaggy in appearance with many spreading hairlike scales, shining pale brownish and whitish; legs darker ventrally, metathoracic leg whitish, tibia with a conspicuous fringe of white hairs along dorsal margin. Forewing: Length about 3.5 times width, truncate in appearance owing to broad terminal and tornal fringe. Ground color dark brown; a thin, distinct white line along Cu from base to just before middle of wing, an upturned white mark at end of cell; considerable whitish overscaling (largely lost in worn specimens) as follows: dorsal area below longitudinal white line, a blotch before tornus joined to white line by a curving stripe, costal area on distal half, meeting terminal area whitish above middle. Rather distinct ground color areas are thus defined on fresh specimens above longitudinal white line, continuing outward as a band to just above tornus, interrupted only by the white mark at end of cell, a large round spot on middorsum; all obscure in worn specimens. Fringe of mixed brownish and whitish. Underside brown, some ochreous scaling below cell and along dorsum. Fringe brown with a white spot at midtermen. Hindwing: Slightly narrower than forewing; costa excavated in distal half; apex blunt. A pale ochreous, dorsal scale brush arising at base of costa. Ground color dark brown, costal area paler. Fringe broad, equal to one-half the membrane width; pale ochreous with a basal brown band. Underside brown, veins and fringe pale ochreous. Abdomen: Dorsal scaling blackish brown, ventral and genital scaling ochreous-brown. Genitalia as in Figure 53 (drawn from plesiotype, San Francisco, JAP prep. no. 1500; five preparations examined); uncus deeply notched; gnathos dentate posteriorly, with roughened lobes anteriorly; basal processes short, broad.

MAP 15.–Geographical distribution of Ethmia brevistriga Clarke.

E. b. brevistriga E. b. aridicola Powell

FEMALE.–Length of forewing 5.4 to 6.0 mm. Essentially as described for male, but specimens available mostly worn and not showing as much whitish pattern. Antenna shaft about two-thirds as thick as in male. Hindwing without costal scale brush; underside generally paler. Genitalia similar to E. coquillettella (Figures 177–179); papillae anales heavily sclerotized basad, more broadly so ventrally; sterigma a simple band, subtended by a lightly sclerotized basal neck of the ductus bursae which bears four or five tiny spurs; ductus bursae entirely membranous with about eight loops in a loose spiral; signum a narrow fold bearing numerous, variable, scattered flat spurs (Figures 108, 181, drawn from plesiotype San Francisco, JAP prep. no. 2724; two preparations examined).

TYPE DATA.–Bodega Bay, California, May 2, 1937 (E. C. Johnston); holotype male in U.S. National Museum.

GEOGRAPHICAL DISTRIBUTION.–Immediate coastal areas of central California, from Sonoma County to San Luis Obispo County (Pismo Beach).

FLIGHT PERIOD.–March to mid-May.

HOST PLANT.–Phacelia distans Benth. A detailed biology is given elsewhere (Powell, 1971).

Ethmia brevistriga aridicola Powell, new subspecies

Plate 5h; MAP 15

Ethmia scylla is a moth in the family Depressariidae. It is in California, United States.

The length of the forewings is 5.8–7.2 mm (0.23–0.28 in). The ground color of the forewings is pale grayish brown, clouded and marked by whitish scaling. The ground color of the hindwings is gray-brown. Adults are on wing from late February to early April.

The larvae feed on Collinsia heterophylla. They feed in the flowers of their host plant.