Type species: Nautilus costatus Fichtel and Moll, 1798 (*1124), p. 47 ( non Nautilus (Ortho-cerasi) costatus Batsch, 1791) = Spincterules anaglyptus Loeblich and Tappan, nom. nov. herein: OD(M).Spincterules de Montfort, 1808 (*2176), p. 222. Spincterulus de Blainville, 1827 (*248A), p. 268 (err. emend.).

Test lenticular, planispiral and involute, biconvex, close coiled, rapidly enlarging cham­bers extending to the umbilicus without a central boss, sutures slightly curved, depressed, periphery carinate; wall calcareous, perfo­rate, optically radial, hyaline, surface with numerous low costae radiating from the apertural region to the previous suture, those of earlier chambers being secondarily thickened and more elevated, ribs also may break up into rows of knobs; apertural face smooth, with elevated margins, aperture radiate at the peripheral angle, the slit in the median posi­tion on the apertural face being enlarged and ovate in outline. Holocene; off Morocco, Northwest Africa.

Remarks: As Nautilus costatus Fichtel and Moll, 1798, type species of Spincterules, is a junior homonym of Nautilus (Orthoceras) costatus Batsch, 1791, the former is here re-named as Spincterules anaglyptus, nom. nov.