Abstract
Six nephtyid species were identified from samples collected off the west coast of Saudi Arabia. Two of these species had been previously reported for the Red Sea (Inermonephtys aff. inermis, Nephtys palatii), three are new records (Aglaophamus lobatus, A. cf. verrilli, Micronephthys stammeri) and one is new to science (Inermonephtys aramco). Inermonephtys aramco was collected in the southern region of the Red Sea at depths between 60 and 83 m. It is characterized by the presence of branchiae from chaetiger 15 or 16, well-developed parapodial prechaetal lamellae, broadly rounded notopodial postchaetal lamellae and rudimentary neuropodial postchaetal lamellae. The species Nephtys palatii is transferred to the genus Micronephthys. Based on the current finding, the previously known bathymetric range of Micronephthys stammeri is extended from 4-7 to 17 m, and occurrence depths for N. palatii are given for the first time (4-90 m). Full descriptions are included for all species except M. stammeri. An identification key for all the species known to occur in the Red Sea is provided.