The INA is a card file and online reporting system maintained at the Silva Center for Phycological Documentation of the University Herbarium, University of California, Berkeley. It contains nearly 200,000 names of algae (in the broad sense). The BPU is a card file containing bibliographic references pertaining to algal taxonomy.
| Name | Author | Source | Citation | Year |
|---|---|---|---|---|
| Ceratium fusus var. inaequale ('inaequalis') | Schröder | Mitt. Zool. Stat. Neapel | 14: 17, no fig. | 1900 |
| Ceratium tripos f. claviceps | Schröder | Mitt. Zool. Stat. Neapel | 14: 16, pl. 1: fig. 17n | 1900 |
| Ceratium tripos f. longissimum | Schröder | Mitt. Zool. Stat. Neapel | 14: 16, pl. 1: fig. 17i | 1900 |
| Ceratium tripos f. palmatum ('palmata') | Schröder | Mitt. Zool. Stat. Neapel | 14: 16, pl. 1: fig. 17o-p. | 1900 |
| Ceratium tripos f. undulatum ('undulata') | Schröder | Mitt. Zool. Stat. Neapel | 14: 16, pl. 1: fig. 17k-m. | 1900 |
| Ceratium tripos var. gibberum | (Gourret) Schröder | Mitt. Zool. Stat. Neapel | 14: 15 | 1900 |