The Yellow-tail (Euproctis similis) has a wingspan of 35–45 mm, the female usually noticeably larger than the male.
All parts of the adults are pure white, apart from a large tuft of yellow hairs at the tip of the abdomen (larger in the female).
When disturbed, the Yellow-tail raises the end of its abdomen.
The male has a distinctive dark gray or blackish spot on the inner edge corner of the forewing; sometimes also a smaller spot at the wing tip and near the base of the forewing.
The female has at most a few faint dark spots in the inner edge corner.
The male has feathery, bipectinate antennae, the female has simple threadlike antennae.
The Yellow-tail flies at night in July and August and is attracted to light, especially the males.

Caught in my self made moth trap.

A male. In my yard, Hilversum, The Netherlands, 10 September 2023