Brachionycha borealis (Smith) 1899

Asteroscopus borealis Smith, 1899, Canad. Ent., 31:25.

Diagnosis: Brachionycha borealis is a distinctive species with a number of peculiarities. First it is the only species of Brachionycha in North America, flying in the early spring in the boreal forest of the United States and Canada. Females are very rare in collections. The large gray, rounded wings and the pectinate antennae in the male should readily separate it from any other North American species of Noctuidae. The dorsum of the abdomen is covered with long, very coarse hairs. Wing length from base to apex: (male mean = 21.62 mm., standard deviation = 0.41 mm., n = 10), (female mean = 26.02 mm., standard deviation = 4.24 mm., n = 2).

Distribution: (See Map Below) Specimens of this species are rare in collections. I have seen it from Michigan, Wisconsin, Manitoba, Alberta, Saskatchewan, Quebec, Ontario, Pennsylvania, and northern West Virginia. Brachionycha borealis is possibly more common that it seems, but its early spring flight habits may keep it from being noticed more. The species has a tendency for melanism. "Normal" specimens are a medium gray while melanics are suffused with black.

Identification Quality: Excellent

Larva: J.D. Lafontaine has kindly supplied me with color slides of the larva. The larva is large, translucent green. The abdominal segments are distinctly separated and segment eight has a noticeable hump. The segments are covered with white spots. The spiracles are white with red rims. The most distinctive marking is a white line running from the eighth abdominal spiracle back along the anal shield and forward to the spiracle on the other side. The thoracic legs are red. The head is translucent green.

Foodplants: Specimens in the CNC were reared from Vaccinium angustifolium (Ericaceae). The closely related Old World species nubeculosa feeds on a variety of deciduous trees, apparently preferring birch.

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