Diagnosis. – Gastrochaenolites with an irregular vaselike shape that has a roughly circular cross-section throughout the length of the structure. Aperture is narrow. Proximal (upper) portion of the structure is long and neck-like. Diameter of the structure expands downward from the neck and then contracts again to give the main part of the structure an irregularly ovoidal form. Distal (basal) portion of the structure is irregular in shape and is tapering in most cases but may be at in others.
G. oelandicus resembles the amphora-shaped ichnospecies Amphorichnus papillatus Ma¨nnil, 1966b, which was described from lower Ordovician strata in Estonia, but G. oelandicus lacks the characteristic nipple-like projection at the bottom of the trace fossil, which Maännil (1966b) asserted to be diagnostic of A. papillatus. Most importantly, A. papillatus clearly is a burrow, not a boring.