Chrysallida emaciata: General description (after 640 shells from 29 localities). — The shape of the shell is slender, cylindrical, with short convex whorls and a blunt top. The protoconch is of type B. There are four or five (rarely six) short and convex whorls. The suture is deep and rather wide, inclined. The ribs are narrow and curved, somewhat flexuous on the last whorl. They are vertical or slightly prosocline and continue as far as the last spiral on the base. Dependent on the number of ribs, the interstices may be broader or narrower than the ribs. On the initial whorls there is one spiral ridge at about 1/3 of the height from the abapical suture. Occasionally a second spiral is present in the suture. The last whorl has two spirals, the lower one on the same level as the upper side of the aperture, the other at some distance above it. Apart from these spiral ridges, fresh shells also show a spiral microstructure between the ribs over the whole surface. On the ribless part of the base there are about ten very thin, wavy spirals, close together and much narrower than the real spiral ridges, although coarser than the microsculpture. The aperture is rather broadly oval. There is a tooth, generally only visible on turning the shell somewhat to the left.
Length 1.4-2.4 mm, LW 43-55%, A 23-32%, L/B 2.3-3.1, B/b 1.4-1.5 (based on 56 shells).

AS Chrysallida emaciata
Habitat: it lives in the mesolittoral and infralittoral zones. Found plentifully during washing of brown algae, collected all over the Mediterranean . Common enough.
Notes: this species is vitreous in aspect, very stretched, cylindrical in outline (it reminds a Turbonilla juvenile shell). Whorls convex, suture deep. Protoconch is type B. Axial ribs, narrower than interspaces, are sinuous and they are extended up to the base. Ribs are crossed by one spiral cord, over suture, placed at 1/3 of height of any whorl, while last whorl has got two of them. A fine spiral microsculpture is visible at the base as far as fresh specimens are concerned. Aperture roundish in form, columellar lip bent with one small tooth, external lip simple. C. suturalis is a similar species, however it has whorls less convex, axial ribs vertical and it has no spiral streaking at the base. Also Turbonilla juvenile specimens are easily separable having a different protoconch, whorls less convex and teeth missing. In conclusion, Graphis albida has an outline like C. emaciata but it is slimmer, with more whorls, a different protoconch and a spiral sculpture much finer crossing the whole surface.
As proved by Gaglini (1992), imaged shells of Monterosato's collection, denominated Chrysallida annexa, are included in the variability field of this species. Average measures of adult specimens are around 2 mm in height.

Chrysallida emaciata: The species most resembling C. emaciata is not a Chrysallida, even not a member of the Pyramidellidae: Graphis albida (Kanmacher, 1798). Apart from the apparent difference in the protoconch (not coiled), Graphis albida is even more slender, has more whorls and many thin spirals (thinner than the main spirals of C. emaciata) over the total height of all whorls. There is no tooth. No Turbonilla resembles C. emaciata, because of the differences in the protoconch, in the convexity of the whorls and by the general absence of a tooth. All Chrysallida showing spiral ridges on the base of the shell, are much more conical and much coarser, with flat whorls. C. sigmoidea is much heavier and larger, has more wavy ribs and only thin spirals, close together (no main spirals). There is no tooth. Of all Chrysallida C. suturalis resembles C. emaciata most, but the former has flat whorls and, at least on the initial whorls, almost straight and vertical ribs. There are no spiral ridges on the base.

Chrysallida emaciata: The entire Mediterranean area and the south coast of Portugal.