[6] Pilumnus hirtellus is found from the North Sea to Morocco, the Azores, Madeira, the Canary Islands and the Cape Verde Islands, as well as in the Mediterranean and Black Seas.

[7] It is limited by the occurrence of hard frosts, violent storms and pollution.

Showing that regions near the Mediterranean like Sado Estuary, Portugal display that the species has a high frequency occurrence of 48.33%.

[5] It can be found on various substrates, including muddy, sandy and rocky bottoms, under stones and even among the holdfasts of seaweeds.

[3] In the Black Sea, this species prefers stony areas with abundant algae and mussels.