Genus
Ptychagnostus Jaekel, 1909
List of species
Classification
| Organism group | Biota |
| Kingdom | Animalia |
| Phylum | Arthropoda |
| Subphylum | Trilobita |
| Order | Agnostida |
| Family | Ptychagnostidae |
| Genus | Acidusus |
| Goniagnostus | |
| Onymagnostus | |
| Pentagnostus | |
| Ptychagnostus | |
| Species | affinis |
| Genus | Tomagnostus |
| Triplagnostus | |
| unranked | Lejopyge |