Dipatulichnus rotundus Nielsen et Nielsen, 2001

Description– Pairs of closely spaced, sub-circular, sub-cylindrical unconnected holes c. 400 μm apart. The diameters, averaging 119 μm, of these openings are constant and perpendicular to the substrate surface.

Remarks– The difficultly in isolating this ichnospecies is the similarity of each of the cylindrical-like ‘holes’ to Oichnus simplex Bromley, 1981, and the semi-interpretive aspect of one of the diagnostic features as it relates to proximity of these biogenic holes.

Diagnosis. Pair of biogenic holes, unconnected, but situated in the same skeletal substrate. Each hole has a simple cylindrical form, oriented perpendicular to the substrate surface. Both external and internal openings are sharp and circular in outline.