Ichnology of Late Cretaceous echinoids from the Maastrichtian type area (The Netherlands, Belgium) – 1. A healed puncture wound in Hemipneustes striatoradiatus (Leske)

A test of the holasteroid echinoid Hemipneustes striatoradiatus (Leske) from the upper Maastrichtian (Upper Cretaceous) of quarry 't Rooth (Bemelen, southern Limburg, The Netherlands) is perforated by a pit on the mid-line of the adoral surface. This structure is large (maximum width 13.5 mm, depth 5.8 mm), rounded pentagonal in outline, bilaterally symmetrical and irregularly conical with a flat base. It may be an invertebrate trace fossil, although not the boring Oichnus Bromley or an embedment structure, or it may represent a healed puncture wound produced after a failed predatory attack by a marine vertebrate such as a bony fish or a mosasaur. If the latter, the shape of the pit may have been modified by the echinoid healing the wound; alternately, the tooth that caused the wound may have been truncated