Entobia astrologica Mikuláš, 1992

Description: Asystem of borings consisting of one chamber widely open towards the surface and a dense network of exploratory threads. The chamber is roughly spherical or ellipsoidal, but it does not show a geometrical regularity, which is characteristic of the early stages of E. solaris. The size of chambers ranges from 2.5 to 11 mm. Exploratory threads run zig-zag and are roughly radial. They either start from the aperture or from the whole surface of the chamber even into the substrate. The threads abundantly ramify dichotomously ("chondritically"). Their diameter varies between 0.1 and 0.5 mm and in some cases it decreases gradually from the chamber to the proximal end. The small number of finds does not permit to distinguish the individual growth phases and to discuss the variability of individual ichnospecies in more detail either. Remarks: E. astrologica differs from E. solaris in a less regular shape of the chamber. The exploratory threads differ in their zig-zag course, ramifying and their presence within the substrate. From another form, one-chamber E. gigantea Bromley and D'Alessandro 1989, our form differs in smaller dimensions and the existence of a prominent chamber even in earlier ontogenetic stages (in E. gigantea a marked oval chamber is constituted as late as in phase D).