Virtual thin sections in transverse view of the dorsal ridge spine of Romundina stellina (P.11714).

(A1-A3) Three-dimensional reconstruction created from low-resolution (7.46 micron) synchrotron data. Red lines on B1 indicate approximate locations of A1-A3. (B1-B4) 3D reconstructions of the spine illustrating its overall morphology in (B1) left lateral, (B2) right lateral, (B3) anterior, and (B4) posterior, (C) dorsal, and (D) ventral views. Scale bars are 1500 μm. Abbreviations are: cc, central canal; eo, embedded odontode; pch.b, perichondral bone; s, sediment; vc, vascular canal; vco, vascular canal opening.