Scalloped hammerhead – Sphyrna lewini

Scalloped hammerhead, Scalloped Hammerhead, Sphyrna lewini
Size: 430 cm
Depth: 0 - 1043 m
Weight: 152400 g
Water Type: Marine, Brackish
Toxicity: Toxic hazard unknown
Red List Status: Vulnerable (VU)
Temperature: °F - 80.6 °F (°C - 27°C)

Algeria, American Samoa, Andaman and Nicobar, Angola, Anguilla, Antigua and Barbuda, Argentina, Aruba, Ascension Island, Australia, Azores Islands, Bahamas, Bahrain, Bangladesh, Barbados, Belize, Benin, Bermudas, Bonaire, Brazil, Brunei Darussalam, Cambodia, Cameroon, Canary Islands, Cape Verde, Cayman Islands, Chile, China, Christmas Island, Cocos Islands, Colombia, Congo, Cook Islands, Corsica Island, Costa Rica, Cuba, Curaçao, Democratic Republic of the Congo, Djibouti, Dominica, Dominican Republic, Ecuador, Egypt, El Salvador, Equatorial Guinea, Eritrea, Fiji, France, French Guiana, French Polynesia, Gabon, Galapagos Islands, Gambia, Ghana, Gibraltar, Grenada, Guadeloupe, Guam, Guatemala, Guinea, Guinea-Bissau, Guyana, Haiti, Hawaii, Honduras, India, Indonesia, Iran, Iraq, Israel, Italy, Ivory Coast, Jamaica, Japan, Jordan, Kenya, Liberia, Madagascar, Madeira Islands, Malaysia, Maldives, Martinique, Mauritania, Mauritius, Mayotte, Mexico, Micronesia, Monaco, Montserrat, Morocco, Mozambique, Myanmar, Namibia, New Caledonia, Nicaragua, Nigeria, Oman, Pakistan, Palau, Panama, Papua New Guinea, Peru, Philippines, Portugal, Puerto Rico, Qatar, Saba, Saint Kitts and Nevis, Saint Lucia, Saint Martin, Saint Vincent And The Grenadines, Samoa, São Tomé and Príncipe, Sardinia Island, Saudi Arabia, Senegal, Seychelles, Sierra Leone, Singapore, Sint Eustatius, Somalia, South Africa, South Korea, Spain, Sri Lanka, Sudan, Suriname, Taiwan, Tanzania, Thailand, Timor-Leste, Togo, Tonga, Trinidad and Tobago, Turkey, Turks and Caicos Islands, Tuvalu, United Arab Emirates, Uruguay, USA, Venezuela, Vietnam, Virgin Islands, Western Sahara, Yemen

The Scalloped Hammerhead, scientifically known as Sphyrna lewini, is a remarkable shark species distinguished by its distinctive hammer-shaped head. This characteristic feature, along with its overall robust physique, makes it easily recognizable within the marine environment.

Description & Characteristics

The Scalloped Hammerhead, Sphyrna lewini, can reach a maximum size of 430.0 cm. Its defining feature is the flattened, hammer-shaped head, which is broader than its body. The head is adorned with scalloped edges along its margins, giving rise to the species’ common name. This unique head shape is believed to enhance sensory perception, allowing the shark to detect prey more efficiently. The Scalloped Hammerhead has a streamlined body, with two dorsal fins, two pectoral fins, two pelvic fins, an anal fin, and a caudal fin. Its body is covered in dermal denticles, small, tooth-like scales that provide protection and reduce friction during swimming.

Habitat and Occurrence

The Scalloped Hammerhead, Sphyrna lewini, exhibits a wide distribution across the globe. They are typically found in warm, tropical, and subtropical waters, often inhabiting coastal areas, oceanic islands, and continental shelves. Their depth range extends from the surface to a remarkable 1043.0 meters. This species is a common inhabitant of both nearshore and offshore waters, including the epipelagic (surface to 200 meters), mesopelagic (200-1000 meters), and bathypelagic (1000-4000 meters) zones. Their ability to thrive in such a range of depths highlights their adaptability to various marine environments.

Taxonomy

The Scalloped Hammerhead, Sphyrna lewini, belongs to the Class: Elasmobranchii, which encompasses cartilaginous fishes. This class includes sharks, rays, and skates. The Scalloped Hammerhead is further classified within the Order: Carcharhiniformes, a diverse group that includes the majority of sharks. Finally, it is a member of the Family: Sphyrnidae, which comprises the hammerhead sharks, characterized by their distinctive cephalofoils. This taxonomic classification underscores the unique lineage and evolutionary adaptations of Sphyrna lewini within the broader realm of sharks.

Feeding

The Scalloped Hammerhead, Sphyrna lewini, is an opportunistic predator with a diverse diet. It feeds primarily on a variety of fish, including large fish, coralfish of all kinds, crustaceans such as lobsters, and even smaller sharks. This feeding behavior reflects its adaptability and ability to exploit various prey resources within its habitat. The hammerhead’s unique head shape plays a significant role in its feeding strategy. The wide separation of its eyes allows for a wider field of vision, aiding in prey detection. Additionally, the sensory organs located on its head are believed to help it locate prey through electroreception and mechanoreception.

Associated Species

Image References

Leave a Comment