RNames - Scheme: Ordovician time slices (Bergström et al., 2009) (10)
Binning results
| Structured Name | Oldest | Youngest |
|---|---|---|
| Aalenian | Ka4 | Hi2 |
| Abak | Ka4 | Ka4 |
| Abarsaj | Ka4 | Hi2 |
| Aber Mawr Shales | Dw2 | Dw3 |
| Aber-Corris | Ka4 | Ka4 |
| Abercastle | Fl1 | Fl3 |
| Abercwmeiddaw | Ka4 | Ka4 |
| Abereiddi Tuff | Dw3 | Dw3 |
| Abereiddian | Dw2 | Dw3 |
| Acanthochitina barbata | Ka1 | Hi1 |
| Acanthochitina barbata | Ka4 | Hi1 |
| Acanthochitina cancellata | Ka1 | Ka3 |
| Acanthocordylodus festus | Ka1 | Ka1 |
| Acanthodina nobilis | Ka4 | Ka4 |
| Acanthodus lineatus | Tr1 | Tr1 |
| Acanthograptus sinensis | Tr2 | Tr3 |
| Acanthograptus suecicus | Fl3 | Fl3 |
| Acodus delicatus | Tr2 | Tr3 |
| Acodus deltatus / Oneotodus costatus | Tr2 | Tr3 |
| Acodus deltatus / Paroistodus proteus | Tr3 | Fl1 |