Creseis acicula (Rang, 1828) forma acicula (Rang, 1828)
Shell transparent, cross-section circular, surface smooth, extremely long and narrow, tube-shaped, not curved, aperture rounded. Columellar muscle runs free through shell lumen over great distance (between attachment point and point where muscle disappears into visceral mass). With wing protrusions. Embryonic shell differs in shape from that of forma clava by caudal end consisting of oval-shaped embryonic part with one or two ring-shaped swellings cranially. Rear angle of shell 13-14°, shell length: 33 mm, width: 1.5 mm.