Phyllonorycter deserticola Davis & Deschka 2001

Phyllonorycter deserticola

ADULT (Figure 29).—Length of forewing: 2.9–3.8 mm. Small moths, with slender, relatively pale reddish brown forewings mostly traversed by approximately 5 irregularly oblique white bands. Valvae of male genitalia symmetrical, slender, slightly curved ventrad and tapering to an acuminate, relatively sinuate apex.

Head: Vertex rough, with white piliform scales occasionally with a few brownish scales intermixed; frons smooth, lustrous white. Antenna white; apex of each segment lightly ringed with brown. Labial palpus uniformly lustrous white.

Thorax: Dorsum mostly white with a reddish brown spot centered posteriorly; tegula mostly white, with light to heavy suffusion of brown. Venter lustrous white. Forewing variable, light reddish brown, usually with five costal white strigulae and four dorsal white strigulae; second dorsal strigula from base usually confluent with costal first and second strigulae; specimens from California and Utah often with white strigulae more heavily speckled with dark brown tipped scales; reddish bands margined distally with dark brown; elongate, subapical, dark brown spot usually distinct. Fringe pale gray. Hindwing and fringe uniformly pale gray. Legs mostly silvery white, with dark brown suffusion dorsally over tibia and tarsomeres, usually forming two dark dorsal bands on tibia and three on tarsus.

Abdomen: Light to dark reddish brown dorsally, silvery white ventrally; conspicuous sex-scaling absent. Eighth sternum of male moderately elongate and broad; apex broadly round to slightly emarginate (Figure 244).

Male Genitalia (Figures 242, 243): Vinculum broadly V-shaped. Transtilla thickened, quadrate. Valva symmetrical, elongate, moderately slender, tapering to a slightly sinuate, accuminate apex. Anellus completely membranous. Aedoeagus slender, approximately equal to length of eighth sternum, with a minute, subapical lobe.

Female Genitalia (Figures 429, 230): Duct of accessory bursa moderately long, about 0.6× the length of ductus bursae, and arising caudally immediately anterior to moderately broad antrum. Signum a single, round, sclerotized disk bearing a pair of minute spines.

LARVA (Figures 137–150).—Similar to P. nipigon. Length of largest third instar 3.5 mm; head width 0.4 mm. Fifth instar: Length of largest larva 6.2 mm; head width 0.43 mm. A1, A2, and P1 arising distant from adfrontal suture. Apical spines of hypopharynx (Figure 146) reduced. Prothorax with D1 anterior to D2. Pronotum with D1 anterior to D2. Crochets on A3–A5 with 3–5 hooks in caudal row and 5–7 hooks in two anterior rows.

LARVAL MINE (Figure 20).—As illustrated.

PUPA (Figures 151–160).—Maximum length 3.8 mm; width 0.7 mm. Vertex with triangular cocoon cutter similar to P. apparella. Forewing and antenna extending to middle of A6. Hindleg extending to caudal margin of A7. Dorsum of A2–A8 almost completely covered with dense concentration of moderately large to small, scattered spines, the largest situated cephalad; intersegmental surfaces as in Figure 153. Caudal half of sternum A7 with a slightly raised triangular area bearing 3 small stout spines laterally (Figure 156), 2 spines on left side and one on right in single and examined. Cremaster consisting of usually two pairs of widely spaced, short spines; the ventral, subterminal pair the most lateral and most widely separated (Figures 158, 159). A9 with sternum abruptly constricting to A10 (Figure 157).

HOLOTYPE.—California: Inyo Co. Wildrose Canyon, 5500 ft. [1677m], e. larva 11–19 Aug 1977 [e.=emerged], G. Deschka, mine in Populus ?macdouglii Rose [P. x parryi Sarg.], zucht nr. 1293, mine: 10 Aug 1977, USNM slide 30777 (GD 1410), USNM.

PARATYPES.—MEXICO: DURANGO: 25 km S. of Durango, 1890 m: 2, mine: 17 Aug 1980, e. larva 18–30 Aug 1980, G. Deschka, mine in Populus sp. zucht nr. 1531, GD slide 1705. SONORA: 8 km S. of Nogales, 1080 m: 2, mine: 22 Aug 1980, e. larva 22 Aug–2 Sep 1980, G. Deschka, mine in Populus sp., zucht nr. 1536, GD slide 1703. UNITED STATES: CALIFORNIA: Inyo Co., Wildrose Canyon, 5500 ft. [1677]: 3, 5, mine: 10 Aug 1977, e. larva 11–19 Aug 1977, G. Deschka, mine in Populus ?macdougalii Rose [P. x parryi Sarg.], zucht nr. 1293, slides USNM 22910, 22911. Madera Co., 5 mi [8 km] E. Delhi, McConnell State Park: 1, 12 Jul 1969, e. 24 Jul 1969, P. Opler, JAP 69G26, Populus fremontii. Riverside Co., Joshua Tree Nat'l Monument, Yucca Valley, 1070 m: 8, 7, mine: 17 Jul 1977, e. larva 19–29 Jul 1977, G. Deschka, mine in Populus macdougalii Rose [P. x parryi Sarg.], zucht nr. 1270, GD slide 1401, 1402. San Bernardino Co., Death Valley, Scotty's Castle: 2, mine: 12 Aug 1977, e. larva 13–20 Aug 1977, G. Deschka, mine in Populus sp., zucht nr. 1295. San Diego Co., Scissors Crossing: 1, 2, 5 Oct 1967, e. 13–17 Oct 1967, P. Opler, JAP67K69, Populus fremontii, DRD slide 3733. Sutter Co., Feather River, nr. Nicolaus: 2, 2, 1 Sep 1981, e. 10–18 Sep 1981, D. Wagner, JAP 81J1, Populus fremontii. 1 mi [1.626 km] E. Nicolaus, Feather River: 4, 2, 31 Aug 1981, e. 18 Sep., D. Wagner, JAP81J1, Populus fremontii, USNM slide 30382. Tulare Co., Porterville: 11, 3, 13–20 Jun 1968, 1, 8, 21–24 Jun 1968, C. Eads, e. cottonwood, slides 17090, 17463, 18055. COLORADO: Jefferson Co., Denver: 2, 2, 11–16 Jul 1901, Dyar 1038 [=17183], cottonwood, USNM slides 17464, 30882, 30884. NEVADA: Churchill Co., Fallon: 3, 3, 25 Sep 1975, R. Alcorn, e. Populus fremontii, slide 30818. Swingle Bench: 7, 9, 1 Oct 1975, R. Bechtel, e. Populus fremontii, slide 28429. Douglas Co., Topaz Lake: 4, 1, 14 Dec 1978, J. Doyen, under Populus bark, DRD slide 3735. NEW MEXICO: Eddy Co., Atoka: 1, mine: 22 Jul 1978, e. larva 5 Aug 1978, G. Deschka, mine in Populus fremontii S. Wats., zucht nr. 1339, GD slide 1543. Otero Co., White Sands Nat. Monument, Great Dunes, 1250 m: 6, 4, mine: 22 Jul 1978, e. larva 1–9 Aug 1978, G. Deschka, mine in Populus fremontii [deltoides] wislizenii S. Wats., GS slide 1544. Sandoval Co., Rio Grande and Rt 44, about 40 km N. of Albuquerque: 1, 1, 5 larvae, 31 Jul 1989, e. Aug 1989, D. Davis, DRD 668.1, e. Populus fremontii, slides 30459–30461. Soccoro Co., San Acacia, 1555 m: 1, 4, mine: 23 Jul 1978, e. larva 4–9 Aug 1978, G. Deschka, mine in Populus fremontii [deltoides] wislizenii S. Wats., zucht nr. 1341, GD slides 1545, 1712. ~2 km E. of Escondido: 1, 25 Jul 1989, e. 8 Aug 1989, D. Davis, DRD 668, e. Populus fremontii. TEXAS: Brewstcr Co., Castolon, 661 m: 20, 17, mine: 24 Jul 1987, e. larva 29 Jul–5 Aug 1987, G. & L. Deschka, mine in Populus fremontii S. Wats., zucht nr. 1988, GD slides 2235. UTAH: Washington Co., Zion National Park: 7, 4, 17 Oct 1940, R. Furniss, e. cottonwood, slide 20428. Wayne Co., Capitol Gorge, Fremont River: 1, 2, mine: 10 Aug 1978, e. larva 16–21 Aug 1978, G. Deschka, mine in Populus fremontii S. Wats., zucht nr. 1359, GD slide 1558. Paratypes in BMNH, DLW, GD, UCB, and USNM.

HOST (Table 1).—Populus fremontii S. Wats, P. deltoides wislizenii S. Wats., P. x parryi (P. freemontii x trichocarpa), Populus sp.

PARASITOIDS (Table 2).—Eulophidae: Pediobius sp., Pnigalio flavipes Ashm., Sympiesis marylandensis Girault, Sympiesis sp.

FLIGHT PERIOD.—Late July to early October; bivoltine, with the second generation overwintering.

DISTRIBUTION (Map 3).—This species occurs in restricted, mostly arid habitats over a broad portion of the southwestern United States and northern Mexico from southern Utah to Durango and west to northern California.

ETYMOLOGY.—The specific name is derived from the Latin desertum (a waste place) and cola (dwelling in), in reference to the general habitat of this species.

Phyllonorycter deserticola is a moth of the family Gracillariidae. It is found in restricted, mostly arid habitats over a broad portion of the south-western United States and northern Mexico from southern Utah to Durango and west to northern California.

The length of the forewings is 2.9-3.8 mm. Adults are on wing from late July to early October in two generations, with the second generation overwintering.

The larvae feed on Populus species, including Populus fremontii, Populus deltoides wislizeni, Populus x parryi (Populus freemontii x Populus trichocarpa). They mine the leaves of their host plant.