Doto pinnatifida is one of the largest species of the genus Doto (max. size 3,0 cm in length). It is characterised by black tipped tubercles on the sides of the body and on the cerata; a few of these tubercles on the dorsum. The rhinophore sheaths have a series of black spots around the edges.
The only other Doto species with tubercles on the body is Doto tuberculata. This species is smaller.
Doto pinnatifida feeds exclusively on the hydroid Nemertesia antennina. The spawn is laid on this hydroid.
Doris pinnatifida Montagu, 1804
Doto armoricana Hesse, 1872
Doto pinnatifida var. nigra Eliot, 1910
Doto pinnatifida var. papillifera Eliot, 1910