Abstract
Sediment samples were collected from the intertidal zone at various localities on the southern shores of the Red Sea and the marine interstitial ciliate fauna was studied. Eighteen species were identified in live specimens and after protargol impregnation; 14 of them represent new records for the Red Sea fauna. The distribution of each species was compared to that in similar habitats worldwide. The present study increases the total known number of ciliate species in the Red Sea to 43.