Adult: "Diagnosis (habitus). Dark tooth-like spots along costa, marking beginning of antemedial and postmedial lines, distinguish
Z. dentata from all but
Z. lituralis,
Z. martha, and some
Z. protumnusalis. The presence of a third (subapical) costal spot, (where the subterminal line meets the costa), usually present in
Z. lituralis, is absent in
Z. dentata; the grayer ground color and uneven subterminal line also distinguish
Z. lituralis from
Z. dentata.
Z. martha is distinguished from
Z. dentata by its darker ground color, weakened subterminal line, darkened distal 1⁄4 of forewing, and its larger size. The discal spot of
Z. dentata tends to be larger, more vertically elongate, and the distal side is often more concave than that of
Z. protumnusalis and others. The antemedial line of
Z. dentata is more toothed (zigzagged) than that of most other similarly-sized, brown North American
Zanclognatha (but see discussion). The postmedial line is often abruptly-angled outward over the radial veins in
Z. dentata, whereas in
Z. protumnusalis and
Z. martha, this part of the postmedial tends to be more evenly rounded. In
Z. protumnusalis the subterminal line is more likely to be outwardly edged with pale scales (in both wings) and
Z. protumnusalis tends to have more tan in the ground color, thinner and crisper costal spots, and lacks the blurry patch of fuscous scales basad of the postmedial line, which extends from the inner margin to the cell, that is present in many
Z. dentata. In most specimens of
Z. protumnusalis the ground color of the hindwings tends to be noticeably paler than that of the forewings, especially through the radial area." - David L. Wagner, Timothy L. McCabe (2011)
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Larvae: See "Preliminary key to
Zanclognatha larvae"
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