specimen of
C. n. euphemia from above The
wingspan is 70–85 mm;
C. n. euphemia is distinctly larger (around 90 mm). The forewings are brownish gray above, evenly dark from base to tip or with the center somewhat darker, and varying geographically between somewhat paler and browner in the aridland population and darker gray marked with brown in the eastern individuals (see
Gloger's rule). The hindwings are conspicuously colored in various hues of orange with roughly
concentric black markings above. Their basal area carries a dense covering of thin dark hairs which stretches along the dorsum, making this area appear more brownish or reddish. Through the hindwing center runs a black band from the leading almost to the trailing edge; a similar but wider band runs close to and parallel with the termen from apex to tornus. The border of the black bands with the fairly narrow area of orange between them is not even, but has some deep and irregular scallops. The outer rim of the hindwing is lighter yellow than the rest; along the wing veins the outer black band extends to the termen as faint blackish stripes. The undersides are pale yellowish orange with black bands. As is typical for the hickory/walnut-feeding
Catocala of North America, both foreleg and hindleg
tibiae of this species are spiny, and the tarsi carry four rows of irregular rows of spines each. The
old wife underwing (
C. palaeogama, see
below) is most easily distinguished by the thickly hairy hindwing bases – below as well as above, forming a fuzzy black patch on the upperwings – and the less scalloped, more angular orange/black border on the hindwing upperside. It is also distinctly smaller, with little or no overlap in wingspan. Adults of the nominate subspecies are found from June to October;
C. n. euphemia adults are on the wing from July to August. The
caterpillars feed on
Juglandeae trees of the
genera Juglans (walnut trees) – such as the
butternut tree (
J. cinerea) – and
Carya (hickories). The westernmost population apparently does not feed on
Carya (which is rare or absent in their range), and seems effectively to be limited to
Arizona black walnut (
J. major), and perhaps
Texas black walnut (
J. microcarpa) and their
hybrids. ==Classification==