The red-necked footman is a small moth that is mostly charcoal grey or deep dark brown (fresh specimens almost black), but has a conspicuous orange thorax, part of which is visible behind the black head as an orange-red collar. The hindwings are brownish grey. The
antennae and legs are black and the end of the abdomen is yellowish orange or golden yellow. The wings are tightly folded together around the body and have pleated, squared-off ends. The
wingspan is and the length of the forewings is . (MHNT) Atolmis rubricollis - Mont Lachens (Var) - male dorsal.jpg|♂ (MHNT) Atolmis rubricollis - Mont Lachens (Var) - male ventral.jpg|♂ △
Wilhelm Neuburger named
Romanian specimens as the synonym
Atolmis flavicollis; these were less dark brown and with a light yellow instead of a red collar. == Life cycle ==