Semilaoma lidgbirdensis, also known as the Mount Lidgbird pinhead snail, is a tiny species of land snail that is endemic to Australia's Lord Howe Island in the Tasman Sea.

[2] The depressedly turbinate shell of the mature snail is 0.8–0.9 mm in height, with a diameter of 1.5–1.6 mm, and a low spire.

The sutures are weakly impressed, with closely spaced, sinuate radial ribs.

It has an ovately lunate aperture, and a very narrow, sometimes closed, umbilicus.

[2] The snail is common and widespread across the island in lowland forest, rainforest and scrub.