Shallow-water Rissooidea from Oman (Arabian Sea) (Caenogastropoda: Rissoidae, Lironobidae, Barleeiidae)

Eighteen species of Rissooidea from Oman (Arabian Sea) are treated here. The presence of Alvania albachiarae Perugia, 2021, Alvania masirahensis Perugia, 2021, Omanimerelina eloiseae Moolenbeek & Bosch, 2007, and Merelina iohannae Perugia, 2021, recently described for the same geographical area, is confirmed, with the addition of some details to their description. Some new species are also described and illustrated, belonging to the genera Alvania Risso, 1826, Crisilla Monterosato 1917, Simulamerelina Ponder, 1985, Subonoba Iredale, 1915, Voorwindia Ponder, 1985, Merelina Iredale, 1915, and Barleeia W. Clark, 1853.