Phragmatobia fuliginosa, the ruby tiger, is a moth of the family Erebidae.
Phragmatobia fuliginosa can be found in the Palearctic realm. It is present in most of Europe, in North Africa, Russia, Central Asia, Tibet, and in northern areas of North America.
This species inhabits moist open forest and meadow areas, mixed hardwood forests at low elevations, open meadows or prairies and in agricultural areas at low elevations. It is common on low-growing plants, on high-roads, railway embankments and waste fields. On warm days in the winter the larvae sometimes leave their hiding-places and are then found on fieldpaths and roads, running about quickly.
Phragmatobia fuliginosa has a wingspan of 35–45 mm. The ruby tiger has the thorax and forewings dark reddish brown with a blackish comma-shaped spot at the apex of the cell, edged with carmine. Hindwings are carmine, more or less hyaline in the costal area, with more or less confluent black spots before the margin and at the apex of the cell.
The name-typical form ''Phragmatobia fuliginosa L. has the forewing rather densely scaled and the hindwing bright rose-red with distinct black spots. Underside strongly suffused with purple-pink.
The eggs are reddish grey. The larva is light or dark grey with a black brown head. The entire body is covered with foxy red hairs. These hairs are always more black brown in placida, and sometimes so in fuliginosa. The pupa is black with the abdomen marked with yellow in the segmental incision.
