Galapagos Species Checklist

Sphyrna lewini (Griffith & Smith, 1834)

tiburón martillo, Scalloped hammerhead

Photo: Inti Keith, CDF.
Photo: Inti Keith, CDF.

Size: At least 4.2 m. Silver-gray to gray-brown, fading to white underside. Underside tips of pectoral fins dusky. Rear edge of vental fin straight.

Habitat: Areas of deep water near dropp-offs. Form large schools of 400 individuals, swimming well organized










Taxon category: Accepted

Syn.: Cestracion leeuwenii Day, 1865, Cestracion oceanica Garman, 1913, Sphyrna diplana Springer, 1941, Zygaena erythraea Klunzinger, 1871, Zygaena indica van Hasselt, 1823, Zygaena lewini Griffith & Smith, 1834, fide Appeltans et al. (2010)

Taxon origin: Native




Distribution: Tropical waters, less frequent in temperate regions; know from sothern California to Ecuador including Galapagos. California to Northern Peru and all the offshore islands of the Eastern Pacific. Circumtropical.


  • Grove, J.S. Lavenberg, R.J. (1997) The Fishes of the Galapagos Islands. Stanford University Press, Stanford California. 862 pp.
  • Humann, P. Deloach, N. (2003) Reef Fish Identification - Galapagos. New World Publication, Inc. Florida USA & Libri Mundi, Quito, Ecuador, 226 pp.
  • Appeltans, W. Bouchet, P., Boxshall, G.A., Fauchald, K., Gordon, D.P., Hoeksema, B.W., Poore, G.C.B., van Soest, R.W.M., Stöhr, S., Walter, T.C., Costello, M.J. (eds.) (2010) World Register of Marine Species (WoRMS). Available online at
  • IUCN (2010) IUCN Red List of Threatened Species. Version 2010.1. <>. Downloaded on 26 April 2010.
  • Baum, J. et. al. (2007) Sphyrna lewini
  • McCosker, J.E. Rosenblatt, R.H. (2010) The fishes of the Galápagos Archipelago: an update. Proc. Calif. Acad. Sc., Ser. 4, vol. 61, Suppl. II, no. 11: 167-195.
  • Edgar, G.J. Fariña, J.M., Calvopiña, M., Martínez, C. & Banks, S. (2002) Comunidades submareales rocosas II: Peces y macroinvertebrados móviles. In: Danulat, E. & Edgar, G.J. (eds.) (2002): Reserva Marina de Galápagos. Línea Base de la Biodiversidad. Fundación Charles Darwin/Servicio Parque Nacional Galápagos, Santa Cruz, Galápagos, Ecuador, p. 68-97.
  • Constant, P. (2007) Marine Life of the Galapagos. The Diver's guide to Fishes, Whales, Dolphins and marine Invertebrates, 307 pp.
  • Hickin, N. (1979) Animal life of the Galapagos. Ferundune Books, Faringdon, U.K., 236 pp.

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