E. axena was first described by Edward Meyrick in 1884 using three specimens collected on grassy slopes at 4,500 ft at Arthur's Pass and named Scoparia axena.[2] Meyrick gave a fuller description of the species in 1885.[3] The lectotype specimen, collected at Arthur's Pass, is held at the Natural History Museum, London.[4]
Description
The wingspan is 19–26 mm. The forewings are variable in colour, but the markings are always of the same form. They are sometimes mixed with ochreous-greenish, or partially blackish. In males, the markings are suffused with blackish towards the costa. The hindwings of the males are pale grey, while they are ochreous posteriorly in females.
