Whitefin hammerhead
The whitefin hammerhead (Sphyrna couardi) is a species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of hammerhead shark
Hammerhead shark
The hammerhead sharks are a group of sharks in the family Sphyrnidae, so named for the unusual and distinctive structure of their heads, which are flattened and laterally extended into a "hammer" shape called a "cephalofoil". Most hammerhead species are placed in the genus Sphyrna while the...

, family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Sphyrnidae, found in the tropical waters of the northeastern Atlantic Ocean
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...

, from Senegal
Senegal , officially the Republic of Senegal , is a country in western Africa. It owes its name to the Sénégal River that borders it to the east and north...

 to the Congo region. According to Cadenat and Blanche (1981), some specimens associated with the smalleye hammerhead
Smalleye hammerhead
The smalleye hammerhead or golden hammerhead is a small species of hammerhead shark, family Sphyrnidae, common in the shallow coastal waters of the western Atlantic Ocean from Venezuela to Uruguay. It favors muddy habitats with poor visibility, reflected by its relatively small eyes...

 (Sphyrna tudes) are in fact of the whitefin hammerhead, which would extend the range of this species into the Mediterranean Sea
Mediterranean Sea
The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...

. McEachran and Serret (1986) synonymized this species with the scalloped hammerhead
Scalloped hammerhead
The scalloped hammerhead is a species of hammerhead shark, family Sphyrnidae. Originally Zygaena lewini, it was later moved to its current name. The Greek word sphyrna translates into "hammer" in English, referring to the shape of this shark's head.This shark is also known as the bronze,...

 (Sphyrna lewini).

In appearance the whitefin hammerhead is very similar to the scalloped hammerhead, with a moderately broad, narrow-bladed head (width 21-25% of total length). The front margin of the head is broadly arched, with prominent indentations in the middle and sides. The first dorsal fin
Dorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...

 is tall and falchate (sickle
A sickle is a hand-held agricultural tool with a variously curved blade typically used for harvesting grain crops or cutting succulent forage chiefly for feeding livestock . Sickles have also been used as weapons, either in their original form or in various derivations.The diversity of sickles that...

-shaped), while the pelvic fins are not falchate with straight or slightly concave rear margins. The anal fin is low and long, with a deep notch in the rear margin. The color is blue-grey or grey-brown above, white below. It is distinguished from the scalloped hammerhead in that its head lobes are longer and less wide, the origin of its first dorsal fin are over the pectoral fin midbases, and there are no dark tips on its pectoral fins. Its maximum size is said to be about 3 m long; adult males typically range from 141-184 cm, and adult (gravid) females 230-235 cm.

The whitefin hammerhead mainly feeds on benthic bony fishes, such as eel
Eels are an order of fish, which consists of four suborders, 20 families, 111 genera and approximately 800 species. Most eels are predators...

s and flatfish
The flatfish are an order of ray-finned fish, also called the Heterosomata, sometimes classified as a suborder of Perciformes. In many species, both eyes lie on one side of the head, one or the other migrating through and around the head during development...

es, as well as cephalopod
A cephalopod is any member of the molluscan class Cephalopoda . These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, and a set of arms or tentacles modified from the primitive molluscan foot...

s. As with other hammerheads, they are viviparous, with the young nourished by a yolk sac
Yolk sac
The yolk sac is a membranous sac attached to an embryo, providing early nourishment in the form of yolk in bony fishes, sharks, reptiles, birds, and primitive mammals...

The placenta is an organ that connects the developing fetus to the uterine wall to allow nutrient uptake, waste elimination, and gas exchange via the mother's blood supply. "True" placentas are a defining characteristic of eutherian or "placental" mammals, but are also found in some snakes and...

. Litters range from 24-28 pups, measuring 30-32 cm long or more. It is not known to have attacked people. This species is caught by West Africa
West Africa
West Africa or Western Africa is the westernmost region of the African continent. Geopolitically, the UN definition of Western Africa includes the following 16 countries and an area of approximately 5 million square km:-Flags of West Africa:...

n fisheries but details are unknown.
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