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Which fish order are tetraodontiforms closely related to?

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Scrawled filefish (Aluterus scriptus) — tetraodontiform Scrawled filefish (*Aluterus scriptus*)

Tetraodontiforms are primarily considered to be closely related to the perciforms, which are the typical advanced spiny-rayed fishes.1

While this relationship is well-established, modern research indicates that the classification of the order remains in a state of flux. Some molecular studies suggest that Tetraodontiformes may also be closely related to the Lophiiformes (anglerfishes and their allies), though this hypothesis requires further testing through additional morphological and molecular data.2