Genus
Trigonocyclicus Yeltyschewa, 1963
Classification
| Organism group | Biota |
| Kingdom | Animalia |
| Phylum | Echinodermata |
| Subphylum | Pelmatozoa |
| Class | Crinoidea |
| Organism group | Stemmed echinoderms outgroup (informal) |
| Order | Angulata (col.) |
| Family | Crenatocrininidae |
| Cyclomischidae | |
| Cyclopagodidae | |
| Genus | Acanthodocrinus |
| Constrictocrinus | |
| Cyclocyclicus | |
| Irucrinus (col.) | |
| Pentagonocyclicus | |
| Rookuelacrinus | |
| Rugulosocrinus | |
| Trigonocyclicus | |
| Vialovicystis |