Flagrichnus polyfloges Hook, Radtke, Campbell et Golubic, 2024

Key feature (diagnosis): Flagrichnus polyfloges isp. nov. consists of complex traces composed of a basal fairly isodiametric, sporangia-like swelling having multiple tapered, flameshaped to thread-like extensions that penetrate and permeate the shell (Fig. 9a). The new trace shares several morphological properties with the type ichnospecies F. profundus (WISSHAK & PORTER, 2006, p. 139). Similar to F. profundus and F. baiulus, the new ichnospecies has a simple isodiametric body adhering to the substrate surface. Unlike F. profundus and F. baiulus with simple and forked filamentous extensions (WISSHAK & PORTER, 2006, fig. 4), the new trace is beset by numerous flame-like tapered extensions 2-3 mm wide at base, sufficiently unique to be described as a new ichnospecies: F. polyfloges isp. nov. Light microscopy (Fig. 9a) shows the isodiametric outlines of the lobed sporangial swelling with numerous tapered extensions, which fill the spaces between the substrate crystallites they have preferentially dissolved (HOOK & GOLUBIC, 1993). Adherence to the substrate surface and the flame-like shape of the extensions are best observed on SEM images of resin-casts (Figs. 9b, c)