There are two additional extant order of elasmobranches not found in European waters: the Heterodontiformes (bullhead sharks) and Pristiophoriformes (sawsharks), which are mainly present in the Indian and Pacific oceans.
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The Heterodontiforms appear in the fossil record in the Early Jurassic, well before any of the other Galeomorphii, a group which includes all modern sharks except the dogfish and its relatives.
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