Asteroceras
obtusium, Sowerby 1815
Charmouth,
Dorset Coast.
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Asteroceras
obtusium, Sowerby 1815
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Charmouth,
Dorset Coast.
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| Family ARIETITIDAE Hyatt, 1874 Subfamily ASTEROCERATINAE Spath, 1946 | |
| A zone ammonite of the Upper Sinemurian Substage. | |
| Ribs strong and smooth, curved forward. Whorls high, enlarging rapidly, sides converging above the middle, keel large, prominent, flanked by 2 deep sulci which are lost on outer whorl. Size 15cm across. | |
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