Pterophorus monospilalis is a moth of the Pterophoridae family. It is found in New Zealand, where it is known from the North and South islands and Stewart Island. The wingspan is 21–23 mm. The head, palpi, antennae, thorax, abdomen, and legs are white. The forewings are snow-white with a few brownish-ochreous scales, a blackish dot before the cleft and a minute one on the inner margin before the middle. The hindwings and cilia are snow-white. The larvae feed on young new tips of Pseudopanax arboreus but have also been recorded on Raukaua species and Schefflera digitata.