Pterynotus martinetana, commonly known as fenestrate murex, is a species of sea snail, a marine gastropod mollusk in the family Muricidae, the murex snails or rock snails.
The size of an adult shell varies between 18 mm and 55 mm.
This wide-ranging species is found in the Red Sea -and in the Pacific Ocean in the Philippines, in Hawaii and the Ryukyus, Japan.