Three complementary imaging techniques were used to describe a complex rosette-shaped microboring that penetrates the shells of brachiopods from the Ordovician–Silurian shallow marine limestones of Anticosti Island, Canada. Pyrodendrina cupra n. igen. and isp. is among the oldest dendrinid microborings and consists of shallow and deep penetrating canals that radiate from a central polygonal chamber. The affinity of the tracemaker is unknown, but a foraminiferal origin, as proposed for some dendrinid borings, is rejected. Combining microCT with traditional stereomicroscopy and SEM helped distinguish and quantify fine morphological features while maintaining contextual information of the microboring within the shell substrate. Different imaging techniques inherently bias the description of microborings. These biases must be accounted for as new methods in ichnotaxonomy are integrated with past research based on different methods.

Methods:Micro-computed tomography (MCT) image of brachiopod shell containing pyrite-infilled microborings. Fossil specimen collected from Silurian limestone outcrop on Anticosti Island, Québec, Canada.Formats:The SDT and RAW files can be viewed in VolSuite 3.2 for full 3D rendering, or in ImageJ 1.29x for 2D rendering. The AVI movie file is an animation derived from an ImageJ rendering.