Sea cucumbers are important due to their rotation of key nutrients and high medicinal values. With this in mind and considering the lack of scientific knowledge about them, the purpose of this research was to identify the species of sea cucumber occurring in the intertidal habitats of Hengam Island. Field sampling and surveys were carried out along the coastline based on the geomorphic and habitat characteristics of eight sampling stations in the inter-tidal zone. The samples that were collected from the stations were transferred to the laboratory and identified using morphological keys and a review of their ossicles. By reviewing the literature on the distribution of sea cucumbers, it was determined that a new observation had been made of Holothuria arenicola and Holothuria bacilla from Hengam Island (Persian Gulf).

Although sea cucumber is commercially important, its biology, ecology and dynamic of population have not been known yet in the Persian Gulf. With this respect, this study has been conducted to identify the species present around Hengam Island in the Persian Gulf. Six species of sea cucumber (four species belonging to the genus Holothuria and another two species belonging to the genus Stichopus) were collected on the sub-tidal zone of Hengam Island (Persian Gulf) via SCUBA diving at depths of 5–15 m in March–July 2012. The species identification was made using morphological keys and review of their ossicles.