This is a tracking category for taxonomy templates containing anomalous ranks in the table showing the taxonomic hierarchy. There's an anomaly if, when working down the taxonomic hierarchy, a higher rank appears after a lower one (e.g. family after subfamily). Anomalous ranks will be shaded in red. If the last row has an anomalous rank, the page will be put into this category by Module:Autotaxobox#taxonomyList.

(Note: it is not an error if an ichno- or oo-taxon has a normal parent at the same rank, e.g. an oofamily may have a family as its parent, and an ichnogenus a genus.)