This species has been found only in the North Island and has been collected in the Northland, Auckland, Whanganui and Wellington regions.

The preferred habitat of this species is wetlands and heathlands including gum fields in Northland.

This species was described by Edward Meyrick in 1897 from a specimen collected in Wellington and obtained from George Hudson.

Forewings rather light reddish-brown : veins irrorated with grey- whitish and fuscous; lower end of reniform indicated by a fuscous dot, preceded and followed by a minute whitish dot : cilia light brown-reddish.

Hindwings fuscous, somewhat lighter towards base : cilia pale brownish, tips whitish.

[5] Both the male and female I. micrastra lack the faint dark line on the forewing termen of I. sapiens specimens that connect the vein ends.

[6] It is found only in the North Island and has been collected in the Northland, Auckland, Whanganui and Wellington regions.