Male. — 23-25 mm. Forewings narrow, hindmargin rather strongly sinuate; dull white, slightly sprinkled with dark fuscous; a curved dark fuscous median streak from inner margin near base almost to apex, sharply defined above, suffused beneath; a black dot in disc, and a row of dots on hindmargin. Hindwings elongate, narrow, apex broadly projecting; white; a blackish dot in disc, and a row on hindmargin.[6]
Distribution
This species is endemic to New Zealand.[2][10] Its range is in North Canterbury, Mid Canterbury, South Canterbury, Mackenzie, Central Otago and Otago Lakes.[11] Other than the type locality, specimens have been collected near the foot of Mount Hutt,[6] the Winchmore Irrigation Research Station near Ashburton,[12] at the lower slopes of Mount Ida in Otago,[13] Horseshoe Slip on Mount Grey,[14] and Ashley Gorge.[9] It is now possibly extinct on the Canterbury Plains.[11]
Life cycle and behaviour
The life history of T. scissaria is still uncertain.[15] Adults have been collected in late winter at the foot of Mount Ida, though none were collected there after August.[13] This species has also been recorded as being on the wing in June,[14] December[9] and January.[6] It is most commonly seen between the months of May and July.[15] A second generation emerges during the summer months.[15] Although T. scissaria has been collected during the day,[14] it is attracted to light.[9]
The host species of T. scissaria is as yet unknown.[15][11] However, this species has been associated with the tussock grass Poa cita.[14] It has been hypothesised that the host species for T. scissaria larvae may be in the genus Carmichaelia.[15]
