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 Ginglymostoma cirratum
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See text for genera and species. Chordates ( Phylum Chordata) are a group of Animals that includes the Vertebrates together with several closely related Invertebrates Chondrichthyes or cartilaginous fishes are jawed Fish with paired fins paired nostrils scales two-chambered hearts and skeletons made of Cartilage rather Elasmobranchii is the subclass of Cartilaginous fish that includes Skates rays (batoidea, and sharks (selachii. The order Orectolobiformes, also collectively known as the carpet sharks because many members have carpet-like patterned markings includes a number of familiar types of Theodore Nicholas Gill ( March 21, 1837 – September 25, 1914) was an American Ichthyologist, Mammalogist, |
Nurse sharks are cosmopolitan carpet sharks belonging to the family Ginglymostomatidae. In Biogeography, a Biological category of living things is said to have cosmopolitan distribution if this category can be found almost anywhere around the world The order Orectolobiformes, also collectively known as the carpet sharks because many members have carpet-like patterned markings includes a number of familiar types of Common in shallow, tropical and subtropical waters of the western Atlantic and eastern Pacific, the family comprises three genera each with one species. The Pacific Ocean is the largest of the Earth 's Oceanic divisions They are benthic sharks, characterised as being sluggish and docile. The benthic zone is the ecological region at the lowest level of a Body of water such as an Ocean or a Lake, including the sediment surface and some sub-surface Nurse sharks typically attack humans only if directly threatened.
The largest species, called simply the nurse shark Ginglymostoma cirratum, may reach a length of 4. The nurse shark, Ginglymostoma cirratum, is a shark in the Nurse sharks family the only member of its Genus Ginglymostoma. 3 m; the tawny nurse shark Nebrius ferrugineus is somewhat smaller at 3. 2 m, and the short-tailed nurse shark Pseudoginglymostoma brevicaudatum is by far the smallest at just 75 cm in length. The first of the three species may reach a weight of 110 kg. Yellowish to dark brown in colour, nurse sharks have muscular pectoral fins, two spineless dorsal fins (the second of which is smaller) in line with the pelvic and anal fins, and a tail exceeding one quarter the shark's body length. The Anatomy of Fish is primarily governed by the physical characteristics of Water, which is much denser than air holds a relatively small amount of dissolved A dorsal fin is a Fin located on the backs of some Fishes Whales Dolphins and Porpoises as well as the (extinct The Anatomy of Fish is primarily governed by the physical characteristics of Water, which is much denser than air holds a relatively small amount of dissolved The Anatomy of Fish is primarily governed by the physical characteristics of Water, which is much denser than air holds a relatively small amount of dissolved
The mouths of nurse sharks are most distinctive; it is far ahead of the eyes and before the snout (sub-terminal), an indication of the bottom-dwelling (benthic) nature of these sharks. The benthic zone is the ecological region at the lowest level of a Body of water such as an Ocean or a Lake, including the sediment surface and some sub-surface Also present on the lower jaw are two fleshy barbels, chemosensory organs which help the nurse sharks find prey hidden in the sediments. A barbel on a Fish is a slender whiskerlike tactile organ near the Mouth. Behind each eye is a very small circular opening called a spiracle, part of the shark's respiratory system. Spiracles are small openings on the surface of some Animals that usually lead to Respiratory systems In Elasmobranchs ( Sharks and The serrated teeth are fan-shaped and independent; like other sharks, the teeth are continually replaced throughout the animal's life.
Nurse sharks are nocturnal animals, spending the day in large inactive groups of up to 40 individuals. Hidden under submerged ledges or in crevices within the reef, the nurse sharks seem to prefer specific haunts and will return to them every day. In nautical terminology a reef is a rock, sandbar, or other feature lying beneath the surface of the water (six fathoms or less at low water By night, the sharks are largely solitary; they spend most of their time rifling through the bottom sediments in search of food. Their diet consists primarily of crustaceans, molluscs, tunicates, and other fish, particularly stingrays. Structure of crustaceans As Arthropods crustaceans have a stiff Exoskeleton, which must be shed to allow the animal to grow ( Ecdysis or molting Molluscs are animals belonging to the phylum Mollusca. There are around 250000 extant Species within the phylum with an estimated 70000 Tunicate, also known as urochordata, tunicata (and by the common names of urochordates, sea squirts, and sea pork) is the Fish are aquatic Vertebrate animals that are typically ectothermic (previously Cold-blooded) covered with scales, and equipped with two Dasyatidae is a family of rays, cartilaginous marine Fishes related to Skates and Sharks Dasyatids are common in tropical
Nurse sharks are thought to take advantage of dormant fish which would otherwise be too fast for the sharks to catch; although their small mouths limit the size of prey items, the sharks have large throat cavities which are used as a sort of bellows valve. In this way nurse sharks are able to suck in their prey. Nurse sharks are also known to graze algae and coral. Algae ( sing. alga are a large and diverse group of simple typically Autotrophic organisms ranging from Unicellular to Multicellular forms Corals are Marine organisms from the class Anthozoa and exist as small Sea anemone –like Polyps typically in colonies of many
The mating season runs from late June to the end of July. Most nurse sharks are ovoviviparous, meaning the eggs develop and hatch within the body of the female, where the hatchlings develop further until live birth occurs. Ovoviviparous Animals develop within eggs that remain within the mother's body up until they hatch or are about to hatch The gestation period is six months, with a typical litter of 30-40 pups. Gestation is the carrying of an Embryo or Fetus inside a Female Viviparous Animal. The mating cycle is biennial, as it takes 18 months for the female's ovaries to produce another batch of eggs. The young nurse sharks are born fully developed at about 30 cm long in Ginglymostoma cirratum. They possess a spotted coloration which fades with age.
The name nurse shark is thought to be a corruption of nusse, a name which once referred to the catsharks of the family Scyliorhinidae. The cat sharks or catsharks are a family ( Scyliorhinidae) of Sharks with over 110 Species recorded The nurse shark family name, Ginglymostomatidae, derives from the Greek: from gynglimos meaning "hinge" and stoma meaning "mouth". Greek (el ελληνική γλώσσα or simply el ελληνικά — "Hellenic" is an Indo-European language, spoken today by 15-22 million people mainly
Genera and species
- Genus Ginglymostoma
- Genus Nebrius
- Genus Pseudoginglymostoma (proposed family Pseudoginglymostomatidae)
See also
External links
- FishBase entry on Ginglymostomatidae
- Nurse Shark Facts & Pictures
- MarineBio: Nurse shark, Ginglymostoma cirratum
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