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Rhynchotrema
fossil brachiopod genus
- Related Topics:
- Ordovician Period
- lamp shells
- fossil
Rhynchotrema, extinct genus of brachiopods, or lamp shells, found as fossils in Middle and Late Ordovician rocks (the Ordovician Period lasted from 505 to 438 million years ago). The shell is small and distinctive for its strongly developed ribbing. Rhynchotrema is a useful Ordovician index, or guide, fossil.