Suborder (Animalia): Tetraodontoidei

Suborder Tetraodontoidei (Gymnodontes) 4 tooth plates, 2 in each jaw; skin bearing small erectile spines. Family Triodontidae (threetooth puffers). Most primitive member of the superfamily, the only species to retain even the pelvic bone of the pelvic fin apparatus.

Reference: Britannica.com