Rosalina is a genus of foraminifera included in the rotaliid family Rosalinidae.
Rosalina has a smooth plano-convex to concavo-convex trochospiral test in which the chambers are rapidly enlarging and all visible on the convex spiral side and subtriangular and strongly overlapping on the umbilical side, the final chamber taking up about one-third of the circumference.
Sutures on the spiral side are depressed and oblique, curving back at the periphery.
The umbilicus is open, partly covered by triangular umbilical flaps extending from each chamber of the final whorl.
The aperture is a low interiomarginal arch near the periphery on the umbilical side, with narrow bordering lip.