Abstract In this paper, two species of cotylean Platyhelminthes are recorded for the first time from Qeshm Island, Persian Gulf, Iran. Pictures are taken from living specimens to illustrate shape and colour, and stained sections and drawings are used to describe shape and organisation of some organs. Morphological characters of Persian Gulf specimens of Tytthosoceros lizardensis Newman & Cannon, 1996 are compared to those of the type specimens of this species.