The shell is minute, very fragile, narrow and transparent, usually almost cylindrical or slightly conical. The protoconch is blunt, more or less planispiral and smooth, a little different from that of the Pyramidellidae, with a very small nucleus, rapidly increasing diameter and one whorl (more or less) which can show a clear separation from the teleoconch. It is assumed that there is a "jaw apparatus" similar to that of Ebala, but there is no information about the species of the genus Murchisonella and as there is lack of material, no comparative study has been performed for this difficult and poorly known character.
We have examined the heterostrophic protoconch in broken shells of Murchisonella and our conclusion is that the initial part of the spire is a little immersed, but not like the proto-conchs of type C typical in Odostomia and in Chrysallida, in which this part is deeply immersed. In the present case the initial part is visible, but subsequently the spire rises slightly and covers a small part of the earlier formed spire In this situation we can measure the nucleus as is done to compare species of the Rissoidae. Although the measured diameter of this nucleus is a little smaller than the real diameter (due to the small immersion) this measurement is useful for comparison and differentiation between species. The diameter is measured from the external extreme to the opposite part.
The teleoconch is tall-spired with convex whorls, generally more or less keeled and with delicate sculpture, deep suture, rounded aperture, a very narrow columellar callus or glaze reflected towards the exterior, forming a very narrow umbilicus but without "pyramidellid tooth" and the border of the external lip is sharp.
The animal, rarely observed and photographed is translucent whitish, sometimes with a dark pigmentation on the dorsum of the head. The cephalic tentacles are flat and tri-angular elongate, a little divergent; the anterior foot border with a central depression; the eyes are very small, situated behind the tentacles and rather separated from them. The animal is clearly visible through the transparent shell. Inside the shell the initial part of the coloration extends 5-7 whorls, having a different uniform colour which sometimes is formed by a combination of two other colours.