The thin shell is internal and white, usually with squarish-oval shape when viewed from above. The opening is large and wide, the upper outer edge of the opening is flat and keeled (raised edge); this keel ends in a wing-like extension towards the back of the shell. The top of the shell (apex) is blunted. The shell has a pattern consisting of pits, and these may be connected forming chain-like lines. The shell is not umbilicated. This species is easily recognized because P. angulata is the only philinid in Scandinavia with a wing-like extension of the shell’s outer lip. The size of the shell varies between 0.9–2.3 mm. This species is similar in anatomy to Philine punctata, which differs from this species in having a shell sculpture exclusively of dots, a more rounded shell and an umbilicated shell.
The body is usually creamy orange with small black dots. The head shield is blunt with no middle line. The tissue covering the shell is very thin. There are side extensions of the foot (parapodial lobes).
The radula usually consists of 16 rows of teeth, with two smaller outer lateral teeth and one large inner lateral tooth on each side. The central (rachidian) tooth is absent. The outer lateral teeth are curved with rounded tips and a broad base. The inner lateral teeth are curved with flattened tips and a broad base, the inner edge is denticulated. The brown gizzard plates are shaped like kidney beans, two paired and one smaller plate with a tip on the surface. Nothing is currently known about the male reproductive system.
Occurs at depths down to 160 m on coarse sand, fine shell sand, and mud as well as coarse sand and shell-gravel.
This species has an amphi-Atlantic distribution. It occurs in the western Atlantic along the north-east coast of the United States, and in the eastern Atlantic is known from Norway southwards along the Faeroes, Shetlands, British Isles, Mediterranean Sea, off Mauretania and the Canary Islands.
Ohnheiser LT og Malaquias MAE (2013). Systematic revision of the gastropod family Philinidae (Mollusca: Cephalaspidea) in the northeast Atlantic Ocean with emphasis on the Scandinavian peninsula. Zoological Journal of the Linnean Society 167(2): 273-326. DOI: 10.1111/zoj.12000.