Taxonomic review of the ichnogenus Helminthopsis Heer 1877 with a statistical analysis of selected ichnospecies

The ichnogenus Helminthopsis Heer 1877 is a relatively simple, unbranched, horizontal, internally unstructured, pre‐ or post‐depositional burrow, or trail, that follows an irregularly sinuous or more commonly an irregularly winding or meandering course. The geometric variation in course, its most significant ichnotaxobase, is invariably complex and has resulted in considerable taxonomic disorder, particularly at the ichnospecific rank. This confusion is compounded by the fact that no diagnoses, and, or, detailed descriptions of several of its historically defined ichnospecies were provided and for other ichnospecies such considerations are ambiguous