Carcharhiniformes

Hiu tanah, atau Carcharhiniformes, merupakan ordo terbesar dari hiu. Dengan lebih dari 270 spesies, carcharhiniformes mencakup sejumlah jenis umum hiu, seperti catshark, swellshark, dan hiu pasir.

Carcharhiniformes
Hiu Karang Sirip Hitam
Taksonomi
Ordo	Carcharhiniformes Compagno, 1977

Anggota dari ordo ini dicirikan oleh adanya membran pengelip di atas mata, dua sirip punggung, sirip anal, dan lima celah insang.

Keluarga dalam rangka Carcharhiniformes diharapkan akan direvisi; recent DNA studi menunjukkan bahwa beberapa kelompok konvensional tidak monophyletic.

Famili

Menurut FishBase, delapan famili dari ordo Carcharhiniformes adalah:

• Carcharhinidae (hiu requiem)
• Hemigaleidae (hiu kacang)
• Leptochariidae (barbeled houndshark)
• Proscylliidae (paus gin catsharks)
• Pseudotriakidae (catsharks palsu)
• Scyliorhinidae (catsharks)
• Sphyrnidae (hiu martil)
• Triakidae (houndsharks)

Famili	Gambar	Nama umum	Genera	Spesies	Deskripsi
Carcharhinidae		Hiu requiem	12	62	Hiu requiem adalah jenis hiu yang hidup berpindah-pindah dan tinggal di laut yang hangat (terkadang juga di air payau atau air tawar) such as the hiu harimau, hiu biru, hiu banteng, dan milk shark. Karakteristik ordo carcharhiniform yang biasa terdapat pada jenis hiu ini meliputi mata bulat dan sirip pektoral yang berada tepat di belakang lima celah insangnya. Kebanyakan spesies ini vivipar, individu baru akan dikeluarkan dalam keadaan seluruh tubuhnya telah berkembang penuh. Kelompok hiu requiem mempunyai ukuran yang bermacam-macam, mulai dari 69 cm panjang hiu hiu sharpnose Australia dewasa, hingga 55 m panjang hiu harimau dewasa. Hiu requiem lah yang bertanggungjawab atas banyak serangan hiu pada manusia.
Hemigaleidae		Weasel sharks	4	8	Weasel sharks are found from the eastern Atlantic Ocean to the continental Indo-Pacific in shallow coastal waters to a depth of 100 m (330 ft). Most species are small, reaching no more than 1.4 m long (4.6 ft), though the snaggletooth shark (Hemipristis elongatus) may reach 2.4 m (7.9 ft). They have horizontally oval eyes, small spiracles, and precaudal pits. Two dorsal fins occur, with the base of the first placed well forward of the pelvic fins. The caudal fin has a strong ventral lobe and undulations on the dorsal lobe margin. They feed on a variety of small bony fishes and invertebrates; at least two species specialize on cephalopods. They are not known to have attacked people.
Leptochariidae		Barbeled houndsharks	1	1	The only species of barbeled houndshark is Leptocharias smithii. It is a demersal species found in the coastal waters of the eastern Atlantic Ocean from Mauritania to Angola, at depths of 10–75 m (33–246 ft). It favours muddy habitats, particularly around river mouths. The barbeled houndshark is characterized by a very slender body, nasal barbels, long furrows at the corners of the mouth, and sexually dimorphic teeth. Its maximum known length is 82 cm (32 in). Likely strong-swimming and opportunistic, the barbeled houndshark has been known to ingest bony fishes, invertebrates, fish eggs, and even inedible objects. It is viviparous, with females bearing litters of seven young; the developing embryos are sustained by a unique globular placental structure. The IUCN has assessed the barbeled houndshark as near threatened, as heavy fishing pressure occurs throughout its range and it is used for meat and leather.
Proscylliidae		Finback catsharks	3	7
Pseudotriakidae		False catsharks	3	4	False catsharks are a small family containing false catsharks and gollumsharks. It contains the only ground shark species to exhibit intrauterine oophagy, in which developing fetuses are nourished by eggs produced by their mother.
Scyliorhinidae		Catsharks	17	>150	Catsharks are distinguished by their elongated, cat-like eyes and two small dorsal fins set far back. They usually have a patterned appearance, ranging from stripes to patches to spots. Most are fairly small, growing no longer than 80 cm (31 in); a few, such as the nursehound, can reach 16 m (52 ft) in length. They are found in temperate and tropical seas worldwide, ranging from shallow intertidal waters to depths of 2.000 m (6.600 ft) or more, depending on species. They feed on invertebrates and smaller fish. Some species are aplacental viviparous, but most lay eggs in tough egg cases with curly tendrils at each end, known as mermaid's purses. The swell sharks of the genus Cephaloscyllium fill their stomachs with water or air when threatened, increasing their girth by a factor of two to three. Some catsharks are called dogfish.
Sphyrnidae		Hiu martil	2	8	Hammerhead sharks are named for the unusual and distinctive structure of their heads, which are flattened and laterally extended into a "hammer" shape called a cephalofoil. Many, not necessarily mutually exclusive, functions have been proposed for the cephalofoil, including sensory reception, manoeuvring, and prey manipulation. Hammerheads are found worldwide in warmer waters along coastlines and continental shelves. Unlike most sharks, hammerheads usually swim in schools during the day, becoming solitary hunters at night.
Triakidae		Houndsharks	9	40	Houndsharks are distinguished by large spineless dorsal fins, an anal fin, and oval eyes with nictitating eyelids. They are small to medium in size, ranging from 37 hingga 220 cm (1,21 hingga 7,22 ft) in adult length. They are found throughout the world in warm and temperate waters, where they feed on fish and invertebrates on the sea bed and in midwater.

Timeline dari genera

Groundsharks, seperti hiu blacknose ini, memiliki membran pengelip yang dapat ditarik menyelubungi mata untuk melindunginya.

Referensi lebih lanjut

• Froese, Rainer, dan Daniel Pauly, eds. (2013) Identifikasi Ikan: Hiu tanah di FishBase. Maret 2013 versi.
• Sepkoski, Jack (2002). "A compendium of fossil marine animal genera". Bulletins of American Paleontology. 364: 560. Diarsipkan dari versi asli tanggal 2012-05-10. Diakses tanggal 2011-05-17. 

Pranala luar

• Ordo Carcharhiniformes