Taming an ichnotaxonomical Pandora’s box: revision of dendritic and rosetted microborings (ichnofamily: Dendrinidae) Author Wisshak, Max text European Journal of Taxonomy 2017 2017-12-29 390 1 99 journal article 21907 10.5852/ejt.2017.390 54438cfa-5f3a-4ee3-85c8-00e453a6d641 2118-9773 3839858 4D1D1CA3-8345-4BA3-9C7C-5EBDD40752CE Calcideletrix flexuosa Mägdefrau, 1937 Fig. 11 Calcideletrix flexuosa Mägdefrau, 1937: 57 , pl. IV, fig. 4. Dendrina brachiopodicola Hofmann, 1996: 80 , pl. 9, figs 1–4 . Clionolithes radicans – Clarke 1908 (partim): 168, pl. 10, pl. 11, fig. 2; 1921 (partim): 88, fig. 71 (drawing based on photograph in Clarke 1908 ). Calcideletrix flexuosa – Häntzschel 1962 : W228, fig. 142-4 (reproduced from Mägdefrau 1937 ); 1975: W124, fig. 77-4b (reproduced from Mägdefrau 1937 ). — Pugaczewska 1965: 76 , pl. I, fig. 3; (?) 1970: 428, pl. I, fig. 2, pl. II, fig. 2 (poor illustrations). — Nadjin 1969: 138 , pl. IV, fig. 4 (reproduced from Mägdefrau 1937 ). — Plewes 1996 (partim): 188, pl. 31, figs 7–8, pl. 33, figs 1–7 , pl. 34, figs 1–4 (pl. 34, figs 5–6 = Dictyoporus nodosus ). — Buatois et al. 2017: 161 , fig. 75B ( holotype ). — Wisshak et al. 2017: 131 , figs 3/4, 4/4. Rosetten-Form G – Hofmann & Vogel 1992: 57 , pl. IV, fig. B. Without name – Reich & Frenzel 2002 (partim): 208, pl. 50, fig. 7. Calcideletrix – Whittlesea 2005: 18 , fig. 3. Dendrina anomala – Rudolph 2014 (partim): 19, fig. 24 (specimen on the left). non Calcideletrix flexuosa – Ghare 1982: 132 , pl. 1, fig. 5 (= Calcideletrix breviramosa ). — (?) Košt’ák 2004: 32, fig. 11 (? Dictyoporus nodosus ). — (?) Stiller 2005: 406 , pl. II, figs 3, 15 (poor illustration). Original diagnosis n/a Emended diagnosis Highly ramified, with most branches remaining roughly the same width up to their tapering ends. Branches ramify in a relatively straight manner, although curves develop at irregular intervals. Branches Fig. 11. Calcideletrix flexuosa Mägdefrau, 1937 . A–C . Holotype in an Upper Cretaceous belemnite rostrum from Misburg, Germany. Close-up in B illustrates anastomosis and two potential points of initial entry (arrows). Close-up in C shows peripheral ramification. D–F . Respective SEM views of an epoxy casts of the holotype of junior synonym D. brachiopodicola Hofmann, 1996 , illustrating the very close morphological resemblance of the trace in a belemnite vs a brachiopod substrate. G . Natural casts in a Devonian brachiopod with several C. flexuosa (original of Clarke 1908 : pl. 10; damaged since original publication). H . Another silicified cast in a Devonian brachiopod shell (reproduced from Clarke 1908 : pl. 11, fig. 2). ramify in such a way as to cover the space between branches almost equally. Anastomosis is rare and restricted to the centre of the trace. Original description Channels strongly ramified, 0.04–0.09 mm in diameter. Only the main channel, at the basis of the shrub, opens to the surface, while the side channels do not penetrate to the surface of the belemnite rostrum. [Translated from German] Supplementary description Based on cast material, Plewes (1996) added the following observations: “Cast material shows that the profile of the branches is rounded and sometimes shows a hint of the bubbly texture reminiscent of, but not as pronounced as that seen in C. anomala . Width of the branches varies between 25 µm and 250 µm , with a mean of 98 µm (n = 18, SD = 50.08). Surface texture may also include hair-like filaments. These are between 1 µm and 2.5 µm in width and vary greatly in length. The loops which form as a result of anastomoses between branches within the main body of the trace vary in size and may enclose other blind ending branches. Branching angle varies greatly but is between 90° and 45°, and branching may be polychotomous or dichotomous. Nodes are sometimes swollen and form rounded irregular edges, especially if the branching point is not a simple dichotomy. The spacing between branches varies but is between 380 µm and 900 µm (n = 9, SD = 245.9).” Hofmann (1996) additionally gave a size range of the junior synonym D. brachiopodicola of 1.3 to 3.7 mm . Type material, locality and horizon Holotype ( Fig. 11 A–C) preserved in rostrum of Belemnitella mucronata from the Upper Cretaceous of Misburg near Hannover , Germany , deposited in the collection of the Institut für Geowissenschaften und Geographie , Halle , Germany ( MLU.Mäg1937.IV.4 ). Remarks Hofmann’s Dendrina brachiopodicola very closely resembles C. flexuosa in morphology and dimensions, and was established as a separate taxon based on its vertically oriented oval gallery cross section only. However, Mägdefrau did not specify the tunnel cross-section and this character alone does not justify its use as the ichnotaxobase for a separate ichnospecies, let alone an ichnospecies within a different ichnogenus, and it is thus regarded as a junior synonym herein.