A wonderfully patterned camaenid landsnail, Amphidromus richardi is endemic to Atauro, a small island about 105km2 in area just north of Dili, northern Timor-Leste (aka. East Timor). It is named in honour of the conchologist and shell dealer Richard Goldberg, in recognition of his active collecting trips and support of landsnail research around the world which led to the discovery of several species new to science, including this one.

Two subspecies exist on the island, the nominal subspecies (shown) is found on small trees on limestone plateau in the lowland costal hills of northern and western Atauro Island, and subspecies A. r. manacocoensis Severns, 2006 is restricted to a damp semi-evergreen forest capping the summit of Mt. Manucoco (elevation 995m) in the southern Atauro Island.

The nominal subspecies is characterised by numerous dark bands and yellow blotches over a robust white shell, A. r. manacocoensis is similar but the shell is much thinner, glossier, and more expanded whorls. Usually A. r. manacocoensis has less patterning and lacks varices completely (whereas specimens of the nominal subspecies often carry one or two varices).

The two subspecies are supposedly completely isolated by unsuitable habitat between the coastal area and the apex of Mt. Manucoco. Although its diet is not clear, it probably grazes on a mixture of algae, fungi, and lichens as known for other Amphidromus species. The nominal subspecies appears to be locally common in its habitat, A. r. manacocoensis is rarer partly due to its more restricted habitat and the fact that it lives high up on the trees and is more difficult to locate.

Virtually all specimens on the market and in the collections are from the original collecting event in December 1996 that led to its description. The patterning is quite variable when viewed over a large series, although most specimens of the nominal subspecies carry similar pattern to the one shown here. The subspecies A. r. manacocoensis seem to have generally less numerous spiral bands.

Adult specimens are very consistent in shell size with the average shell length being around 35mm, very large specimens exceeds 38mm for the nominal subspecies. The subspecies A. r. manacocoensis is slightly smaller with the shell length averaging at around 30mm. – from Chong Chen’s post