Three appear to be a possible error – the higher taxa levels have been entered as “higher taxa” instead of phylum or class (for example), but this may also reflect taxonomic status (being agnathids they can’t speak for themselves, lol). The remaining 17 are orders that match directly to phylum or subphylum. Most of these sit within manky phyla that I never remember the name of, so again may reflect taxonomic uncertainty, but I note that valid taxonomies appear to exist for most of the ones I looked up – so it may be that the authors simply didn’t bother.
Three appear to be a possible error – the higher taxa levels have been entered as “higher taxa” instead of phylum or class (for example), but this may also reflect taxonomic status (being agnathids they can’t speak for themselves, lol). The remaining 17 are orders that match directly to phylum or subphylum. Most of these sit within manky phyla that I never remember the name of, so again may reflect taxonomic uncertainty, but I note that valid taxonomies appear to exist for most of the ones I looked up – so it may be that the authors simply didn’t bother.