The mullein moth belongs to a large moth family, whose members typically have dull forewings and pale or colorful hindwings (Noctuidae). The moth is cryptically marked and easily overlooked when settled on a brown plant stem. It is found in a range of habitats including gardens.
The mullein moth gets its name from its caterpillars which usually feed on mullein plants. The caterpillars advertise themselves with bright colors, warning any predators not to eat them because they taste bad.
Adult moths, they have a wingspan of 45-50 mm, are rarely seen but are on the wing during April and May. They are dark brown at the leading edges of the wings fading to a cream color at the deeply serrated trailing edges.
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I stumbled into the mullein moth caterpillar in our garden yesterday. It was munching on a leaf of a mullein plant which already had several holes.