Ichneutica bromias

I. bromias was first described by Edward Meyrick in 1902 using four specimens collected from Chatham Island.[3] The lectotype specimen is held at the Natural History Museum, London.[3]

Meyrick described this species as follows:[2]

♂ ♀. 31-36 mm. Head and thorax grey, sometimes whitish-mixed, variably tinged with brownish or reddish, and indistinctly marked irregularly with blackish streaks. Antennae in ♂ shortly bipectinated to 3⁄5. Abdomen light grey, sometimes ochreous-tinged. Forewings moderately dilated, costa almost straight, apex obtuse, termen crenulate, obliquely rounded ; grey, puitially whitish-sprinkled, variably and irregularly tinged with purple-brownish, median band and terminal area darker ; a short black median longitudinal streak from base ; a short similar parallel streak from dorsum near base, sometimes obsolete ; first and second lines slender, blackish, waved, nearly obsolete on upper half, fairly distinct and rather nearly approximated on lower half ; spots outlined with black, more or less rosy-brownish, especially reniform, orbicular and reniform sometimes whitish-edged, orbicular semi-oval, incomplete above, claviform subtriangular ; subterminal line white, sometimes interrupted or partially obsolete, with one prominent dentation below middle (on vein 3), near dorsum more conspicuous and preceded by a triangular dark fuscous spot, elsewhere edged with smaller dark fuscous spots : cilia fuscous, mixed with dark fuscous, and indistinctly barred with whitish. Hindwings light fuscous, darker terminally ; cilia whitish, with cloudy dark fuscous line.[3]

The male of I. bromias has a wingspan of between 34 and 42 mm and the female of the species has a wingspan of between 32 and 43 mm.[2] This species is similar in appearance to I. mutans but is darker and duller in appearance.[3] As I. mutans has not been recorded in the Chatham Islands confusion between these two species is unlikely.

This species is endemic to the Chatham Islands of New Zealand.[2][4] I. bromias is found on the Chatham, Pitt and Rangatira Islands.[2]

Adult female I. bromias release pheromones to attract males at the lower temperature of 15 degrees Celsius compared to other species in the Ichneutica genus.[2][5] The adult moths are on the wing from November to March.[2]

The life history of this species is unknown as are the host species of the larvae.[2] Similar to other species in the Ichneutica genus is presumed that the larvae of this species exist on a variety of ground cover or low growing herbaceous plants.[2]