A Field Guide to the Snails of Lord Howe Island

136 Family Punctidae (Pinhead or Dot Snails) Genus Semilaoma Iredale, 1944 Shell. Size: H = 0.7-0.9 mm, D = 1.2-1.6 mm. Colour: Pale gold or yellow to white. Shape: Depressedly turbinate to subdiscoidal with a low to flat spire; whorls rounded, shouldered, or slightly angulate. Sculpture: Protoconch with radial sculpture; teleoconch with fine, closely to moderately closely spaced radial ribs and spiral irae. Aperture: Roundly to ovately lunate. Umbilicus: moderately wide to nearly closed. Animal. Not known. Habitat and occurrence. Widespread across the island. Remarks. This endemic LHI genus is distinguished by its minute size, angulate whorls and very narrow to closed umbilicus. There are currently four valid names in this genus, but one, S. abjecta (Iredale, 1944), is probably a synonym of S. lidgbirdensis and so is not included here. There are several undescribed species in the collections of the Australian Museum identified as belonging in this genus. Malabar Kim’s Lookout Transit Hill Intermediate Hill Mt Lidgbird Mt Gower ▲ ▲ ▲ ▲ ▲ ▲ ● S. costata ● S. laevis ● S. lidgbirdensis