Shell small (maximum dimension about 10 mm), extremely thin (maximum thickness of broken edge 0.05 mm), easily damaged; periostracum thin; whorls 3 to 3.5, rounded; suture deeply channeled, spire height low to moderately high. Peristome complete, contact with previous whorl limited to narrow band; final lip flared but not thickened, reflected near base of columella. Umbilicus narrow to broad, umbilical wall with sharp descending carina that terminates on reflected region of lip at base of columella. Protoconch diameter 250 µm, surface smooth; tip bulbous. Outer edge of first quarter turn of teleoconch compressed, not forming regular curve. Operculum thin, up to 5 whorls, multispiral or with final whorl enlarged to give paucispiral effect.
External anatomy. Snout prominent, eyes lacking, cephalic and epipodial tentacles lacking micropapillae. One to two suboptic tentacles short, posterior to right cephalic tentacle. Gill pectinibranch, leaflets numerous. Sexes separate; male using right cephalic tentacle as copulatory organ; open seminal groove on right tentacle. Jaw. As described for family.
Radula. Rachidian tooth relatively small, with triangular shaft and small overhanging cusp; base of shaft broadly emerging from ribbon. First lateral tooth massive, shaft quadrangular, overhanging cusp large, triangular, with bluntly pointed tip; base of shaft articulating with tooth below, base of shaft buttressed on inner and outer edges; second lateral tooth separated from third by open channel. Second lateral tooth largest in row, with two large cusps, the innermost with triangular cusp matching that of second lateral, the outermost cusp having a more obtuse angle; position of both cusps descending away from rachidian; base with projecting ridge above excavation that accommodates tooth below. Third lateral tooth with long shaft and thick, rounded cusp that projects over the outer cusp of second lateral tooth; base buttressed on inner side by narrow ridge. Fourth lateral tooth with longest shaft and small, beaklike cusp, base buttressed on inner side by projecting ridge. Fifth lateral tooth vestigial, closely ap-pressed to base of fourth lateral tooth.

Choristella species may be recognized on shell characters alone (thin shell, channeled suture, complete peristome, compression of early teleoconch, and descending umbilical carination). The descending umbilical carination may be shared with some skeneiform genera, including Trenchia Knudsen, 1964, as discussed here under rejected species. On shell characters, Choristella may be distiguished from such genera in having a much more deeply channeled suture and by the compression of the early teleoconch.
The radulae of all species examined are closely similar. Some differences that may be apparent in the illustrations for each species can be attributed to wear, rather than interspecific differences. The most useful radular characters for interspecific discrimination are the morphology and relative size of the rachidian tooth.