Nepotilla microscopica

The length of the shell attains 1.3 mm, its diameter 0.7 mm.

(Original description) The very minute, yellowish shell contains 3½ whorls, including a 1½ whorled protoconch, which is large, rounded, and spirally lirate. The two adult whorls are strongly angled at the periphery, from whence to the suture they are flat or concave. The sculpture consists of sharp, narrow, axial ribs, about twelve on the body whorl, which extend from suture to suture, and pass into the aperture. They are widely separated, the interspaces being crossed by a few very faint spiral lirae. The aperture is rather expanded. The siphonal canal is very short. The columella is excavate. The outer lip is strongly varixed. The sinus at the suture is deep and open and bordered by a varix.

This marine species is endemic to Australia and occurs off Tasmania.

• Gatliff, J.H. & Gabriel, C.J. 1916. Additions to the alterations in the Catalogue of the Marine Shells of Victoria. Proceedings of the Royal Society of Victoria 29(1): 106-113
• Powell, A.W.B. 1966. The molluscan families Speightiidae and Turridae, an evaluation of the valid taxa, both Recent and fossil, with list of characteristic species. Bulletin of the Auckland Institute and Museum. Auckland, New Zealand 5: 1–184, pls 1–23

• Hedley, C. 1922. A revision of the Australian Turridae. Records of the Australian Museum 13(6): 213-359, pls 42-56 This article incorporates text from this source, which is in the public domain.
• Atlas of Living Australia: Nepotilla aculeata
• Tucker, J.K. (2004). "Catalog of recent and fossil turrids (Mollusca: Gastropoda)" (PDF). Zootaxa. 682: 1–1295.
• Grove, S.J. (2018). A Guide to the Seashells and other Marine Molluscs of Tasmania: Nepotilla microscopica