Chrysymenia tigillis sp. nov. is described on the basis of a few specimens collected from Dhofar, Sultanate of Oman. The new species is known only from southern Oman, a region of the northern Arabian Sea that is strongly impacted by the upwelling from the summertime monsoon. It is distinguished from other species of the genus by the simple nature of the blades, their dimensions (to 75 cm in length and to 21 cm in width), the rough, bumpy surface of the blades, and the presence of internal struts connecting the inner sides of the blades. A census of the currently recognized species in the genus Chrysymenia is provided.