| Callovian | 
|---|
|
|
| | −205 — – −200 — – −195 — – −190 — – −185 — – −180 — – −175 — – −170 — – −165 — – −160 — – −155 — – −150 — – −145 — – −140 — |  |  |  |  | 
 | 
|
| Name formality | Formal | 
|---|
|
| Celestial body | Earth | 
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| Regional usage | Global (ICS) | 
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| Time scale(s) used | ICS Time Scale | 
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|
| Chronological unit | Age | 
|---|
| Stratigraphic unit | Stage | 
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| Time span formality | Formal | 
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| Lower boundary definition | FAD of the Ammonite genus Kepplerites | 
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| Lower boundary GSSP candidate section(s) |  | 
|---|
| Upper boundary definition | FAD of ammonite species Brightia thuouxensis | 
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| Upper boundary GSSP candidate section(s) |  | 
|---|
In the geologic timescale, the Callovian is an age and stage in the Middle Jurassic, lasting between 165.3 ± 1.1 Ma (million years ago) and 161.5 ± 1.0 Ma. It is the last stage of the Middle Jurassic, following the Bathonian and preceding the Oxfordian.