Allenella formalis, also known as the brown turban pinhead snail, is a species of land snail in the family Punctidae. It is endemic to Australia's Lord Howe Island in the Tasman Sea.
The globosely turbinate shell of the mature snail is 2.5–2.6 mm in height, with a diameter of 3.4–3.6 mm, and a moderately raised conical spire. It is amber to dark brown in colour. The whorls are rounded above and below a slightly angular periphery, with impressed sutures and closely spaced radial ribs. It has an ovately lunate aperture and narrowly open umbilicus. The animal is dark brown with a paler brown sole.[1]
The snail occurs on the summits and upper slopes of the island's southern mountains.[1]