Shells minute to small, often with a high and narrow spire, much resembling Triphoridae by the shape and the sculpture, except that they are dextral and never with a developed posterior siphonal canal.
 

« Mature spire shallowly convex or somewhat carrot-shaped; body whorl sometimes slightly constricted. Sutures weakly impressed, distinct. Protoconch of planktotrophic larval type, clearly demarcated from teleoconch, conical, of about 5 convex whorls. Last half-whorl with a prominent peripheral carina and brephic axial riblets on shoulder. […] Sinusigera* sinus deep, opisthocyrtopisthocline. Teleoconch whorls flat or shallowly rounded, reticulately sculptured with spiral and axial costae with expanded nodular intersections. Three shallowly rounded spirals on spire whorls; a 4th spiral emerging from insertion of outer lip. Base evenly contracted at maturity […]. Columella cylindrical at maturity, usually very solid and swollen, smooth apart from growth lines. Aperture subquadrate. Anterior canal gently inclined away from aperture, not produced, open, notched below. » – B. Marshall: “Cerithiopsidae of New Zealand, and a provisional classification of the family”, New Zealand Journal of Zoology vol.5(1), Wellington 1978, p.82.

*Sinusigera sinus: this term refers to a kind of labial undulation in the larval shells of some Gastropoda. The people who discovered this particularity thought it was a characteristic of adult microshells of a new genus. Due to this misconception, the name Sinusigera was established. You can see a picture of this curious feature in H. L. Kesteven: “The systematic position of Purpura tritoniformis of Blainville”, Proceedings of the Linnean Society of New South Wales vol.26, Sydney 1901, plate XXIX, fig.4.
 

Replacement name for the genus Nanopsis Cecalupo & Robba, 2010, which was described as follows: « Protoconch conical, multispiral; whorls convex, with very weak mid-abapical angulation on last quarter of whorl in some species. Protoconch I with uneven, subsutural granular microprotuberances or apparently smooth. Protoconch II with short, slightly prosocline subsutural axial riblets or axial denticles; 1 suprasutural cord-like spiral followed downward by 1-2 threads present in some species. Transition to teleoconch abrupt, marked by opisthocline sinusigera lip and by the sudden appearance of adult sculpture. Teleoconch bottle-shaped to turriculate; spire more or less elevated, cyrtoconoid or straight-sided; whorls rather depressed, nearly flat-sided; sutures impressed. Last whorl cup-shaped to ovate-cylindrical; base short, convex to flatly obconical, imperforated, with distinct neck. Aperture oval, with short or very short abapical canal inclined to shell axis. Sculpture of collabral ribs overridden by 3 robust spiral cords forming nodes at intersections; a fourth spiral, either weakly beaded or smooth, occurs on last whorl at level of suture; a fifth cord is present on upper base, bounded on both sides (only adapically in some species) by a shallow spiral depression. » – The genus Nanopsis in Cecalupo & Robba: “The identity of Murex tubercularis Montagu, 1803 and description of one new genus and two new species of the Cerithiopsidae (Gastropoda: Triphoroidea)”, Bollettino malacologico vol.46, Milano 2010, p.53. Replaced by the name Costulopsis in Cecalupo & Robba: “Costulopsis nom. nov., a replacement name for the Gastropoda genus Nanopsis Cecalupo & Robba, 2010 (Mollusca: Gastropoda: Cerithiopsidae), preoccupied by Nanopsis Henningsmoen, 1954 (Arthropoda: Ostracoda: Beyrichiidae)”, Bollettino Malacologico vol.55(1), Milano 2019, p.65-67.
 

« Similar to the typical Cerithiopsis, but with only two main cords per whorl. » – F. Sacco: I Molluschi dei terreni terziarii del Piemonte e della Liguria vol.17, Torino 1895, p.67. Protoconch with « two moderate spiral keels on the penultimate whorl, the abapical one becoming concealed by the suture on the last whorl, and of flexuose axial riblets forming a reticulate pattern with the keels » – Bouchet, Gofas & Warén: “Notes on Mediterranean Dizoniopsis (Gastropoda: Cerithiopsidae), with the description of two new species”, Iberus vol.28(2), Barcelona 2010, p.52.
 

« We use the genus Krachia for three European deep-water species which all have two smooth cords encircling the base of the shell. » – Bouchet & Warén: “Revision of the Northeast Atlantic bathyal and abyssal Mesogastropoda”, Bollettino Malacologico suppl.3, Milano 1993, p.605.
 

Shell minute to small, « narrowly conical, subcylindrical or (rarely) ovate. Sutures weakly impressed. » Protoconch: « whorls narrowly or broadly conical or subcylindrical, smooth or axially and/or spirally ribbed, sometimes with a peripheral carina. Teleoconch whorls flat, shallowly convex, or (rarely) shallowly concave. Sculpture highly distinctive, consisting of 3 or more smooth, narrow, spiral cords and fine, numerous, close, interstitial axial lamellae. Anterior canal not or slightly produced, widely open, notched below. » – B. Marshall: op. cit. p.94.