Kuphus melitensis, a new teredinid bivalve from the Late Oligocene Lower Coralline Limestone of Malta

A new species of teredinid bivalve, Kuphus melitensis, is described on the basis of valves, tubes and pallets from the marine Lower Coralline Limestone Formation (Late Oligocene) of Malta (central Mediterranean). The valves are preserved as moulds, the pallets as stalks without an awn. This is the first fossil record of valves and pallets of the genus Kuphus Guettard, 1770. The hard part morphology of the new species is compared with that of its Recent congener, Kuphus arenarius (Linné, 1758). The abundant fossil tube material available has provided not only a documentation of such features as shell impressions, localised swellings, calcareous encrustations, bifurcation, repair, periodic angulation, internal cameration, anterior and internal closure of tubes, but also clarification of the stages of development of its calcareous siphonal tubes. These unique tube features are described and interpreted in the light of the animal’s ability to deposit and resorb calcium carbonate. As all previous fossil Kuphus records are based solely on tubes, they are essentially indeterminate Teredinidae, and only Maltese material is positively identified to species level. From an almost world-wide distribution in tropical and temperate Cainozoic shallow seas, Kuphus is now restricted chiefly to the brackish waters and mangrove swamps of the Indo-Pacific region.