Shell oval-globose with a height/width relationship of 1.4-1.5, foot unforked, radula with formula 1.1.1.
Redescription
Shell, general: Oval - globose, widest slightly more than 1/2 of height from base, smooth except for fine growth lines. Transparent to white. Height to at least 2.6 mm. Height/width 1.4-1.5. About 1.7 teleoconch whorls on a 2 mm high specimen (inferred). Spire: Acuminate with protoconch projecting. Shoulders rounded, separated from preceding whorl by an unrimmed groove.
Aperture: 80-85% of shell height. Widest. 1/4 to 1/3 of height from base. Outer lip hyperbolically rounded in lower 1/3 of shell, running almost straight above until it forms a small arch at top. Inner lip running in a shallow curve from top to 2/3 of way to base, where it joins the columella without or almost without an angle, continuing in almost straight line to base. Umbilicus: Open, 1-2% of shell width, apparently with abapertural rim (difficult to see because the umbilicus is so extremely narrow).
Protoconch: Elongated (in moderate degree) letithotrophic type, smooth, 0.5-0.6 mm wide with 0.75 whorls. Angle between teleoconch and protoconch axis about 150°.
External anatomy: Foot not forked posteriorly. Eyes visible.
Radula: Formula 1.1.1, symmetrical. Prostate gland Unknown

Seems very close to Diaphana paessleri in shell shape and anatomy as far as the latter is known, but has a smaller height/width relationship. The protoconch of D. inflata does not seem so pronouncedly elongated as that of D. paessleri. See also Diaphana paessleri. D. inflata can be distinguished from the other species in the D. paessleri group by its markedly more globose shape.

Type locality Cumberland Bay, South Georgia, 54°11'S, 36°18'W, 252-310 m.
Recent; found only at South Georgia at depths down to 281 m (upper limit unknown, but probably rather shallow) (Strebel 1908 and this study).