Microlepidoptera

Size variable but usually with a wingspread of 20 mm. or less. Wing shape variable, sometimes relatively broad, sometimes narrow and pointed apically. Tibial spurs generally long. Many, especially narrow-winged forms, with a fringe of long hairs on anal margin of HW. Wing venation variable but broad-winged forms usually with 2 anal veins in FW and 3 in HW. This is a large group making up about half of the order; identification of many is often difficult. The families of Microlepidoptera are discussed below in 3 groups:

1. With a distinctive wing shape or scaling (p. 240).

2. Wings relatively broad and more or less rounded apically, FW somewhat triangular, HW usually as broad as or broader than FW, and with 3 anal veins (p. 242).

3. Wings narrow and more or less pointed apically, HW usually narrower than FW and with anal area reduced; a long fringe on anal margin of HW (p. 252).

A few families of Microlepidoptera contain species that fall into 2 of the above groups, but in most families all species in the family can be placed in just 1 of these groups.

Microlepidoptera, Group 1 Wings with distinctive shape or scaling: lobed (Pterophoridae and

Alucitidae), distal margin of HW excavated behind tip, with tip produced (Gelechiidae), or wings with extensive areas devoid of scales (Sesiidae).

PLUME MOTHS Family Pterophoridae

Identification: Small, slender, long-legged, brownish or gray. Wings at rest held horizontal, at right angles to body. FW with 2-4 apical lobes, HW with 3.

Plume moths are common insects, easily recognized by the wing position at rest and the lobed wings; the lobes of the hind wing, with their long fringe, are somewhat plumelike. Plume moth larvae are chiefly leaf rollers or stem borers, and some occasionally damage cultivated plants. The Grape Plume Moth, Pterophorus periscelidactyVus Fitch, is a pest of grape.

MANY-PLUME MOTHS Family Alucitidae Not illus.

Identification: Similar to Pterophoridae, but each wing divided into 6 plumelike lobes.

A single rare species of many-plume moth occurs in the northeastern states. It has a wingspread of about 12 mm.

GELECHIID MOTHS Family Gelechiidae Identification: Small to minute moths. FW narrowly rounded or pointed at apex. HW somewhat trapezoidal, the apex usually prolonged and margin behind apex concave. Head smooth-scaled. Palps long and upcurved, 3rd segment long and tapering. If HW is narrow and pointed apically, then R5 in FW is stalked with R4 and extends to costal margin of wing.

This is one of the largest families of Microlepidoptera, with some 600 N. American species. Many are common moths. Larvae vary considerably in habits; some are leaf rollers or leaf tiers, some are leaf miners, a few are gall makers, and 1 species attacks stored grain. Larvae of Gnorimoschema live in stem galls on goldenrod; the galls are elongate, spindle-shaped, and thin-walled. Larva of the Angoumois Grain Moth, Sitotroga cerealella (Olivier), feeds in the kernels of corn and other grains and often causes serious damage to grain in storage. Larva of the Pink Bollworm, Pectinophora gossypiella (Saunders), attacks the bolls of cotton.

CLEAR-WINGED MOTHS Family Sesiidae See also PI. 12 Identification: Wasplike moths, with extensive areas in wings (especially HW) devoid of scales. FW long, narrow, rounded apically, HW broader; posterior margin of FW and costal margin of HW with a series of interlocking spines.

Aegeriids are day-flying and often brightly colored; many strongly resemble wasps. The sexes usually differ in color, and the male often has more clear area in the wings than the female. Larvae bore in roots, stems, and trunks of various plants and trees. Some species are serious pests of garden crops, orchard trees, or forest trees.

Microlepidoptera, Group 2

Size variable, but wingspread usually 20 mm. or more. Similar to macro-moths (pp. 230 ff.), but HW generally with 3 anal veins and FW with 1A often preserved, at least near wing margin; HW usually as wide as or wider than FW; FW more or less triangular, apically rounded or somewhat square-tipped; tibial spurs usually long.

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