| Isoxyida Temporal range:
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|---|---|
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| Restoration of Isoxys curvirostratus | |
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| Restoration of Surusicaris elegans | |
Scientific classification 
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| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Order: | †Isoxyida Simonetta & Delle Cave, 1975 |
| Family: | †Isoxyidae Vogdes, 1893 |
| Genera | |
| Synonyms | |
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Isoxyids are members of the order Isoxyida and the family Isoxyidae, a group of basal arthropods that existed during the Cambrian period. It contains two genera, Isoxys, with 20 species found worldwide, and Surusicaris known from a single species found in the Burgess Shale of Canada. They are distinguished by their bivalved carapaces and pair of upward curving grasping frontal appendages.