First record of the Triplefin fish, Helcogramma ellioti (Herre, 1944), from the Gulf of Oman, Iran (Blennioidei: Tripterygiidae: Tripterygiinae)

First record of the Triplefin fish (Blenniiformes: Tripterygiidae), Helcogramma ellioti , is reported here based on six specimens collected from Chabahar, northern Gulf of Oman in February 2019. Identification was confirmed based on a series of morphological characters including, a minute supraorbital tentacle, 3-5 symphyseal mandibular pores, a numerous number of scales in lateral line (36-37) and a low number of total lateral scale rows (38-39). Specimens were found in coral reef areas at depths of 1-15m of the Gulf of Oman in the Indo-Pacific region. Compared to the other members of Helcogramma , H. ellioti is regarded as a medium to large body size species (25.0-57.0mm SL). Although several species of triplefin fishes have been reported from the Persian Gulf, but, it is the first record from Tripterygiidae for the Iranian waters of the Gulf of Oman.