Nuculana wolffi: Shell small, inflated. Beaks incurved, situated a little in front of the middle of the shell. Anterior end rather narrowly rounded, posterior end attenuate, drawn out into a moderately pointed rostrum, the apex well down towards the ventral margin. Ventral margin broadly and evenly rounded. The only sculpture consists of irregular growth lines. Surface smooth and shining, covered with a light brown epidermis. Mingle line narrow, meeting at an obtuse angle, 9 teeth in the anterior, 11 in the posterior series. There is a narrow, rather constricted resiliary pit. Pallial sinus slight. Length, 3,6mm.; height, 2,5 mm.; inflation (single valve), 0,9 mm. This species is amply characterized by the small size, lack of definite concentric sculpture and the attenuated posterior outline.