Crassimarginatella solidula is an encrusting bryozoan species, rarely found in the British Isles. The colonies form irregular encrusting sheets that spread over the substrate. Crassimarginatella solidula colonises hard substrates including stones and shells in waters from 5 to 80 m.

The species is predominantly a warm temperate to tropical species found in the Mediterranean, and has only been reported from the southern and western shores of the British Isles.