Sphyrna zygaena (Linnaeus, 1758) .

Smooth Hammerhead. To 4 m (13.1 ft) (Weigmann 2016). Circumglobal; western Pacific Ocean north to Hokkaido, Island, Japan (Dyldin et al. 2018); central California (Miller and Lea 1972) to Gulf of California (Eschmeyer and Herald 1983) to Bahía de San Antonio, Chile (33°35’S (Brito 2004b), including Islas Galápagos (Compagno 1984). Depth: surface to at least 200 m (656 ft) (min.: Compagno 1984; max.: Ebert 2003), and possibly to 420 m (1,640 ft) or more (Weigman 2016).