What is "sigmoilinita"

Sigmoilinita is a miliolid genus (Foraminifera, Protista) with an ovate to fusuform test that becomes flattened with growth. Chambers are tubular, one-half coil in length, at first added in a sigmoiline (S-shaped) series starting at slightly more than 180° apart. the angle gradually decreasing until the later whorls are planispiral. Chambers are numerous, the wall narrow. imperforate, porcelaneous. The aperture at the end of the final chamber. may have a weakly developed tooth