Species
Acidusus atavus (Tullberg, 1880)
Synonymy list
1880 Agnostus atavus n. sp. — Tullberg , pp. 14-15, fig. 1:1a-d
2007 Ptychagnostus atavus (Tullberg, 1880) — Ahlberg et al. , pp. 710, fig. 2:1-12
2023 Acidusus atavus (Tullberg, 1880) — Weidner et al. , pp. 30, fig. 16A–R
Classification
| Organism group | Biota |
| Kingdom | Animalia |
| Phylum | Arthropoda |
| Subphylum | Trilobita |
| Order | Agnostida |
| Family | Ptychagnostidae |
| Genus | Acidusus |
| Species | aculeatus |
| atavus |