
Appearance
The American Dagger Moth has a wingspan of 50 to 65 mm . It is gray to gray-brown with darker markings. It usually has a sharp, double postmedian line, with white in between the two lines. There is a black dash on the anal area of the fore wing. The hind wing is gray with a faint, darker gray median line in the male. The female is similar, except the hind wing is completely dark.
Naming
*''Acronicta americana americana''⤷ ''Acronicta americana obscura''
⤷ ''Acronicta americana eldora''

Behavior
The young caterpillar is densely covered with yellow setae. The older caterpillar's setae are either pale yellow or white. All instars have thin, black setae on the first and third abdominal segments. On the eighth abdominal segment, there is one tuft of black setae. The caterpillar will reach a length 50 mm . Caution should be taken in handling the caterpillar, as the hollow setae may break off in to human skin, releasing a toxin which can produce a rash.References:
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