Allenoconcha retinaculum is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusc in the family Microcystidae.

The shell is sculpted with closely spaced, oblique, arcuate folds, which are more pronounced on the later whorls.

The columella margin is curved at the top, descending very obliquely, and thickened inwardly into a whitish, loop-like lamella, visible through the shell.

The outer lip is sharp, and the aperture is obliquely compressed and slightly elevated.

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