The problematic fossil Jinonicella from the Lower Silurian of Gotland

The minute problematic fossil Jinonicella kolebabai Pokorny, 1978 is described from the Lower Silurian (Wenlock, middle Sheinwoodian) of the När-1 core from southern Gotland. Growth lines indicate that the characteristic tubular snorkel of Jinonicella grew by envelopment of an emargination in the median dorsal aperture and not as a perforation through the dorsal surface of the shell. The direction of shell coiling indicates that Jinonicella kolebabai can not be closely related to scaphopods (?Devonian, Carboniferous-Recent). If it is a mollusc, it may represent an independent adaptation to the infaunal scaphopod mode of life.