This study describes a new species belonging to the miliolid foraminiferal genus Pseudotriloculina. The species Pseudotriloculina hottingeri n.sp. is here described from several locations sampled in the Arabian Gulf. The species is distinguished by its U-shaped chambers arranged initially in an indistinct quadriloculine and later in a pseudotriloculine manner and its porcelaneous wall ornamented with longitudinal or bifurcating costae running along the chambers from the posterior end to the apertural margin. It also has a short, taurus/spur-shaped bifid tooth within a terminal aperture and a broad collar draped on the last chamber. It has a restricted bathymetric and ecological distribution in the Arabian Gulf. It has a depth range of 0.02–17 m, tolerates salinity of 36–52 ppt and temperatures of 27–30°C. Specimens were found in 20 samples out of 78 sampled stations studied in the Arabian Gulf. The species appears to have ecological significance in understanding epibiont-basibiont interactions and can also be used to delineate restricted environments based on its ecological preferences.