Syn-vivo bioerosion of Nautilus by endo- and epilithic foraminiferans (New Caledonia and Vanuatu).

A variety of syn-vivo bioerosion traces produced by foraminiferans is recorded in shells of Nautilus sampled near New Caledonia and Vanuatu. These are two types of attachment scars of epilithic foraminiferans and two forms of previously undescribed microborings, a spiral-shaped and a dendritic one, both most likely being the work of endolithic 'naked' foraminiferans. Scanning electron microscopy of epoxy-resin casts of the latter revealed that these traces occur in clusters of up to many dozen individuals and potentially are substrate-specific.

The Paleozoic evolution of the gastropod larval shell: larval armor and tight coiling as a result of predation-driven heterochronic character displacement.

Early and middle Paleozoic gastropod protoconchs generally differ strongly from their corresponding adult morphologies, that is, most known protoconchs are smooth and openly coiled, whereas the majority of adult shells are ornamented and tightly coiled. In contrast, larval and adult shells of late Paleozoic gastropods with planktotrophic larval development (Caenogastropoda, Neritimorpha) commonly resemble each other in shape and principle ornamentation. This is surprising because habitat and mode of life of planktonic larvae and benthic adults differ strongly from each other.