About Euxoa nigricans Linnaeus, 1761
This species is Euxoa nigricans Linnaeus, 1761. Forewings are black-brown with all markings obscured, or dark red-brown with clearer markings; the edges of the stigmata are finely black; some ochreous scales are present outside the reniform stigma, along the submarginal line, and at the base below the cell. Hindwings are brownish fuscous; the basal half is paler in males. Tutt documented more than 20 aberrations, grouped by colouration as follows: The first two aberrations, both with grey ground colour, are rare: ab. pallida Tutt has a reddish tinge, with lines and stigmata nearly completely gone; ab. flavopallida Tutt is similar but has yellow lines and stigmata. The next five aberrations have pale reddish ground colour: ab. rufa Tutt has pale lines and stigmata; ab. ruris Haw. has yellow markings; ab. obeliscata Haw. has a black cell on each side of the orbicular stigma; ab. striata Tutt has yellow ochreous base, stigmata, lines, and outer nervules; ab. rufovariegata Tutt is mottled red and yellow, with black-edged stigmata. The next five aberrations have dark reddish brown ground colour: ab. rubricans Esp. has paler lines; ab. rufovilis has yellow stigmata and lines; ab. quadrata Tutt is similar to ab. rufovilis but has a square black blotch between the stigmata, matching the feature seen in ab. obeliscata Haw.; ab. ochrea Tutt has faint lines but ochreous stigmata and veins; ab. fuscovariegata Tutt is purplish-brown mottled with ochreous and has a dark blotch between the stigmata. In the next four aberrations, the ground colour is blackish-brown or blackish fuscous, matching the typical form of Euxoa nigricans L.: ab. dubia Haw. has darker lines and stigmata, with a conspicuous wavy submarginal line; ab. fumida is smoky brown with an ochreous reniform stigma and a yellowish submarginal line; ab. marshallana is sooty brown with dark lines and ochreous stigmata; ab. ursina God. has dark lines and stigmata, a submarginal row of wedge-shaped spots, and a whitish outer edge to the reniform stigma. ab. rustica Er. is much smaller than ab. ursina God. with all markings obscured. The last group has black ground colour: ab. carbonea Hbn. has yellowish lines and stigmata; ab. fumata has pale-edged upper stigmata; ab. fumosa F. has a submarginal row of whitish wedge-shaped spots; ab. fuliginea God. is entirely black with only very faint markings. Euxoa nigricans cannot be certainly distinguished from closely related species without expert reference; for further information on identification, see Townsend et al. For a list of recorded food plants, see Robinson, G. S. et al.
