Family Yponomeutidae 
Ermine Moths 
The ermine moths web foliage together. The ailanthus webworm, Afteva punc- 
tella (Cramer), feeds on the foliage of ailanthus throughout the Southern States and 
north to New York and the Lake States. The adult is orange to brownish and has a 
wingspread of 25 to 30 mm. The forewings are bright yellow, and each one has four 
rows of round yellow spots on a blue background. The larvae feed on leaves 
enclosed in frail, silken webs. The pine needle sheathminer, Zelleria haimbachi 
Busck, feeds rather commonly on jack pine in southern Ontario. It may occur in the 
Lake States. 
Family Argyresthiidae 
Argyresthiids 
Moths of this family are small, usually brightly patterned, and have rather broad 
wings. 
The genus Argyresthia contains a number of leafmining species. The adults have 
wingspreads of about 8 to 12 mm. While at rest, their wings are folded close to the 
body, their front legs are extended forward, and their hindlegs are slanted upward at 
45° angles. 
Argyresthia freyella Walsingham is generally distributed in eastern Canada and 
south and west to the Middle Atlantic States and Missouri. Its hosts are redcedar 
and northern white-cedar. The adult is whitish and has a wingspread of about 8 mm. 
The forewings are golden with silvery spots and bands and a black dot at the apex of 
each. The larvae feed in mines that they extend along main branches and 
branchlets. Winter is apparently spent in the mine as a full-grown, yellowish-green 
to green larva, and there is one generation per year. Pupation takes place in the 
spring in cocoons spun on leaves or branches. Damage to ornamentals and nursery 
seedlings appears to be less than that caused by the related species, A. thuiella. A. 
aureoargentella Brower attacks northern white-cedar. It resembles A. freyella ex- 
cept that its cocoons are whiter and larger. 
The arborvitae leafminer, A. thuiella (Packard), feeds on northern white-cedar 
throughout much of the same area as that occupied by A. freyella. The adult is light 
gray to white and has a wingspread of about 8 mm. The forewings are marked with 
brown and there is a black spot in the middle edge of the distal end of each. The 
larva is about 3 mm long. The head and cervical shield are shiny black, the body is 
green with a reddish tinge, and the legs and anal plate are black. Adults appear from 
late May to mid-July, and the female deposits her eggs in the axils of branchlets or 
along the edges of leaves. Newly hatched larvae bore into the leaves and feed in 
them as miners for the rest of the season. Winter is spent in the larval stage in the 
mine and pupation and adult emergence occur in the spring. Outbreaks in Maine 
have severely damaged forest stands of northern white-cedar. Damage to ornamen- 
tals and nursery seedlings is often serious. Heavily defoliated trees may be killed 
(160). The habits of the species of arborvitae leafminers have been discussed 
(1081). 
Larvae of the apple fruit moth, A. conjugella Zeller, bore in the fruit of 
mountain-ash, serviceberry, hawthorn, apple, plum, and cherry in the Northeast. 
The adult is dark gray and has a wingspread of 10 to 12 mm. The forewings are dark 
gray, very slender, crossed by black and silver-white bands, and each bears a 
yellowish-white spot on the outer margin. A. laricella Kearfott, the larch shoot 
borer, larvae bore in the shoots of larch in southern Canada and the Lake States. 
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