No, not Neotropical snails, but still on topic as Placostylus is one of the ‘remote family members’ of the Orthalicoidea. A new paper presents a revision of the New Zealand taxa from this genus (Buckley et al., 2011).
About 20 Placostylus taxa have been described from New Zealand, many of which were subspecies published by A.W.B. Powell. Doubt already existed on these many subspecies, but Buckley et al. have investigated both the shell morphometry and the DNA of all known taxa. Their conclusion is that only three species should be recognized: P. hongii, P. ambagiosus, and P. bollonsi.
Finally, based on their findings, they present suggestions for conservation actions on these endangered snails.
Buckley, T.R., Stringer, I., Gleeson, D., Howitt, R., Attanayake, D., Parrish, R., Sherley, G. and Rohan, M., 2011. A revision of the New Zealand Placostylus land snails using mitochondrial DNA and shell morphometric analyses, with implications for conservation. – New Zealand Journal of Zoology 38: 55-81.