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48-728: A stingray is a type of cartilaginous fish. Stingray or Sting Ray may also refer to: Stingray Stingrays are a group of sea rays , a type of cartilaginous fish . They are classified in the suborder Myliobatoidei of the order Myliobatiformes and consist of eight families: Hexatrygonidae (sixgill stingray), Plesiobatidae (deepwater stingray), Urolophidae (stingarees), Urotrygonidae (round rays), Dasyatidae (whiptail stingrays), Potamotrygonidae (river stingrays), Gymnuridae (butterfly rays) and Myliobatidae (eagle rays). There are about 220 known stingray species organized into 29 genera. Stingrays are common in coastal tropical and subtropical marine waters throughout

96-697: A great amount of granule -filled cytoplasm. The stinging cells of marine stingrays are located only within these lateral grooves of the stinger. The stinging cells of freshwater stingray branch out beyond the lateral grooves to cover a larger surface area along the entire blade. Due to this large area and an increased number of proteins within the cells, the venom of freshwater stingrays has a greater toxicity than that of marine stingrays. Rays are edible, and may be caught as food using fishing lines or spears. Stingray recipes can be found in many coastal areas worldwide. For example, in Malaysia and Singapore , stingray

144-689: A large area named for the Green River, a tributary of the Colorado River . The three separate basins lie around the Uinta Mountains (north, east, and south) of northeastern Utah: Fossil Butte National Monument in Lincoln County, Wyoming is in a part of the formation known as Fossil Lake because of its abundance of exceptionally well preserved fish fossils . The formation of intermontane basin / lake environments during

192-499: A natural occurrence of moissanite (SiC) and 23 other valid mineral species. The beds display a pronounced cyclicity , with the precession, obliquity, and eccentricity orbital components all clearly detectable. This enables the beds to be internally dated with a high degree of accuracy, and astrochronological dates agree very well with radiometric dates. Within the Green River Formation of southwest Wyoming in

240-404: A wide range of feeding strategies. Some have specialized jaws that allow them to crush hard mollusk shells, whereas others use external mouth structures called cephalic lobes to guide plankton into their oral cavity. Benthic stingrays (those that reside on the sea floor) are ambush hunters. They wait until prey comes near, then use a strategy called "tenting". With pectoral fins pressed against

288-534: Is " Dasyatis " speetonensis from the Hauterivian of England , whose teeth most closely resemble that of the extant sixgill stingray ( Hexatrygon ). Although stingray teeth are rare on sea bottoms compared to the similar shark teeth , scuba divers searching for the latter do encounter the teeth of stingrays. Full-body stingray fossils are very rare but are known from certain lagerstätte that preserve soft-bodied animals. The extinct Cyclobatis of

336-634: Is commonly grilled over charcoal, then served with spicy sambal sauce. In Goa , and other Indian states, it is sometimes used as part of spicy curries. Generally, the most prized parts of the stingray are the wings, the "cheek" (the area surrounding the eyes), and the liver. The rest of the ray is considered too rubbery to have any culinary uses. Stingrays are usually very docile and curious, their usual reaction being to flee any disturbance, but they sometimes brush their fins past any new object they encounter. Nevertheless, certain larger species may be more aggressive and should be approached with caution, as

384-405: Is complicated by having two separate ways to take in water to use the oxygen. Most of the time stingrays take in water using their mouth and then send the water through the gills for gas exchange . This is efficient, but the mouth cannot be used when hunting because the stingrays bury themselves in the ocean sediment and wait for prey to swim by. So the stingray switches to using its spiracles. With

432-406: Is now called the Green River Formation are in the journals of early missionaries and explorers such as S. A. Parker, 1840, and J. C. Fremont, 1845. Geologist Dr. John Evans collected the first fossil fish, described as Clupea humilis (later renamed Knightia eocaena ), from the Green River beds in 1856. Edward Drinker Cope collected extensively from the area and produced several publications on

480-732: Is similar to the species Urobatis halleri , differences can be seen in the particular actions of Hypanus sabinus . Seasonal elevated levels of serum androgens coincide with the expressed aggressive behavior, which led to the proposal that androgen steroids start, indorse and maintain aggressive sexual behaviors in the male rays for this species which drives the prolonged mating season. Similarly, concise elevations of serum androgens in females has been connected to increased aggression and improvement in mate choice . When their androgen steroid levels are elevated, they are able to improve their mate choice by quickly fleeing from tenacious males when undergoing ovulation succeeding impregnation. This ability affects

528-513: Is strictly found in Fossil lake only, while Erismatopterus is uncommon in Lake Uinta but common in certain mass mortality layers of Lake Gosiute and absent from Fossil Lake. The various fossil beds of the Green River Formation span a 5 million year period, dating to between 53.5 and 48.5 million years old. This span of time includes the transition between the moist early Eocene climate and

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576-582: The Cretaceous of Lebanon is thought to be a skate that had convergently evolved a highly stingray-like body plan, although its exact taxonomic placement is still uncertain. True stingray fossils become more common in the Eocene, with the extinct freshwater stingrays Heliobatis and Asterotrygon known from the Green River Formation . A diversity of stingray fossils is known from

624-591: The Horn of Africa , whips were made from the tails of big stingrays and these devices inflicted cruel cuts, so in Aden , the British forbade their use on women and slaves. In former Spanish colonies, a stingray is called raya látigo ("whip ray"). Some stingray species are commonly seen in public aquarium exhibits and more recently in home aquaria. Green River Formation The sedimentary layers were formed in

672-452: The atlantic stingray ( Hypanus sabinus ), social groups are formed first, then the sexes display complex courtship behaviors that end in pair copulation which is similar to the species Urobatis halleri. Furthermore, their mating period is one of the longest recorded in elasmobranch fish. Individuals are known to mate for seven months before the females ovulate in March. During this time,

720-503: The breeding season , males of various stingray species such as the round stingray ( Urobatis halleri ), may rely on their ampullae of Lorenzini to sense certain electrical signals given off by mature females before potential copulation . When a male is courting a female, he follows her closely, biting at her pectoral disc. He then places one of his two claspers into her valve. Reproductive ray behaviors are associated with their behavioral endocrinology , for example, in species such as

768-580: The panrays , during the Late Jurassic period, and diversified over the course of the Cretaceous into the different extant families today. The earliest stingrays appear to have been benthic, with the ancestors of the eagle rays becoming pelagic during the early Late Cretaceous . Permineralized stingray teeth have been found in sedimentary deposits around the world as far back as the Early Cretaceous . The oldest known stingray taxon

816-522: The Amazon feed on insects and break down their tough exoskeletons with mammal-like chewing motions. Large pelagic rays like the manta use ram feeding to consume vast quantities of plankton and have been seen swimming in acrobatic patterns through plankton patches. Stingrays are not usually aggressive and ordinarily attack humans only when provoked, such as when they are accidentally stepped on. Stingrays can have one, two or three blades. Contact with

864-528: The Eocene Monte Bolca formation from Italy , including the early stingaree Arechia , as well as Dasyomyliobatis , which is thought to represent a transitional form between stingrays and eagle rays , and the highly unusual Lessiniabatis , which had an extremely short and slender tail with no sting. The mouth of the stingray is located on the ventral side of the vertebrate. Stingrays exhibit hyostylic jaw suspension, which means that

912-734: The Eocene resulted from mountain building and uplift of the Rocky Mountains (late Cretaceous Sevier orogeny and the Paleogene Laramide orogeny ). Tectonic highlands supplied the Eocene sedimentary basins with sediment from all directions: the Uinta Mountains in the center; the Wind River Mountains to the north; the Front Range , Park Range and Sawatch Range of the Colorado Rockies to

960-705: The Green River Formation are housed at the Smithsonian Institution in Washington, D.C. Fish fossils of Diplomystus and Knightia are found in Fossil Lake but not in Lake Gosiute. Only Lake Gosiute has fossils of catfish ( Ictaluridae and Hypsidoridae ) and suckers ( Catostomidae ). The catfish are found mostly in the deepest parts of the lake. Percopsid sand-roller relatives are known from all three lakes, however Amphiplaga

1008-585: The Uinta highland and the Rocky Mountains to the east and north. The lagerstätten formed in anoxic conditions in the fine carbonate muds that formed in the lakebeds. Lack of oxygen slowed bacterial decomposition and kept scavengers away, so leaves of palms, ferns and sycamores, some showing the insect damage they had sustained during their growth, were covered with fine-grained sediment and preserved. Insects were preserved whole, even delicate wing membranes and spider spinnerets. Vertebrates were preserved too, including

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1056-521: The area known as Fossil Lake , two distinct zones of very fine-grained lime muds are particularly noted for preserving a variety of complete and detailed fossils . These layers are an Eocene Lagerstätte , a rare place where conditions were right for a rich accumulation of undisturbed fossils. The most productive zone—called the split fish layer —consists of a series of laminated or varved lime muds about 6 ft (1.8 m) thick, which contains abundant fish and other fossils. These are easily split along

1104-450: The bodies of hard shelled prey. Male stingrays display sexual dimorphism by developing cusps , or pointed ends, to some of their teeth. During mating season, some stingray species fully change their tooth morphology which then returns to baseline during non-mating seasons. Spiracles are small openings that allow some fish and amphibians to breathe. Stingray spiracles are openings just behind its eyes. The respiratory system of stingrays

1152-427: The dog-sized Meniscotherium and Notharctus , one of the first primates. The earliest bats known from complete skeletons ( Icaronycteris index , I. gunnelli , [1] and Onychonycteris finneyi ), already full-developed for flight, are found here. Even a snake, Boavus idelmani , found its way into a lake and was preserved in the mudstone. The first documented records of (invertebrate) fossils from what

1200-615: The east; the Uncompahgre Plateau and the San Juan Mountains to the south and finally, the Wasatch Mountains of Utah and the ranges of eastern Idaho to the west. The lithology of the lake sediments is varied and includes sandstones , mudstones , siltstones , oil shales , coal beds, saline evaporite beds, and a variety of lacustrine limestones and dolomites . Volcanic ash layers within

1248-438: The estimates of recoverable oil has been questioned, back in 2013, by geophysicist Raymond T. Pierrehumbert, who argued that the technology for recovering oil from the Green River oil shale deposit had not been developed and had not been profitably implemented at any significant scale. Green River oil shale is lacustrine type lamosite . The organic matter is from blue-green algae (cyanobacteria) . The unusual chemistry of

1296-679: The fossil fish from 1870 onwards. Ferdinand Vandeveer Hayden (geologist-in-charge of the United States Geological and Geographical Survey of the Territories, the forerunner of the United States Geological Survey ) first used the name "Green River Shales" for the fossil sites in 1869. Millions of fish fossils have been collected from the area, commercial collectors operating from legal quarries on state and private land have been responsible for

1344-487: The layers to reveal the fossils. This thin zone represents some 4000 years of deposition. The second fossil zone, the 18 inch layer , is an unlaminated layer about 18 in (46 cm) thick that also contains abundant detailed fossils, but is harder to work because it is not composed of fissile laminae. The limestone matrix is so fine-grained that fossils include rare soft parts of complete insects and fallen leaves in spectacular detail. Some 35,000 fossiliferous rocks from

1392-498: The majority of Green River vertebrate fossils in public and private collections all over the world. The Green River Formation contains the largest oil shale deposit in the world. It has been estimated that the oil shale reserves could equal up to 3 trillion barrels (480 billion cubic metres) of shale oil , up to half of which may be recoverable by shale oil extraction technologies ( pyrolysis , hydrogenation , or thermal dissolution of kerogen in oil shale). However,

1440-412: The male stingrays experience increased levels of androgen hormones which has been linked to its prolonged mating periods. The behavior expressed among males and females during specific parts of this period involves aggressive social interactions. Frequently, the males trail females with their snout near the female vent then proceed to bite the female on her fins and her body. Although this mating behavior

1488-406: The mandibular arch is only suspended by an articulation with the hyomandibula . This type of suspensions allows for the upper jaw to have high mobility and protrude outward. The teeth are modified placoid scales that are regularly shed and replaced. In general, the teeth have a root implanted within the connective tissue and a visible portion of the tooth, is large and flat, allowing them to crush

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1536-811: The mothers have not been near a male for two years. This suggests some species of rays can store sperm then give birth when they deem conditions to be suitable. The stingray uses its paired pectoral fins for moving around. This is in contrast to sharks and most other fish, which get most of their swimming power from a single caudal (tail) fin . Stingray pectoral fin locomotion can be divided into two categories, undulatory and oscillatory. Stingrays that use undulatory locomotion have shorter thicker fins for slower motile movements in benthic areas. Longer thinner pectoral fins make for faster speeds in oscillation mobility in pelagic zones. Visually distinguishable oscillation has less than one wave going, opposed to undulation having more than one wave at all times. Stingrays use

1584-565: The next-to-lowest zone in the water column ), but some, such as the pelagic stingray and the eagle rays , are pelagic . Stingray species are progressively becoming threatened or vulnerable to extinction , particularly as the consequence of unregulated fishing . As of 2013, 45 species have been listed as vulnerable or endangered by the IUCN . The status of some other species is poorly known, leading to their being listed as data deficient . Stingrays diverged from their closest relatives,

1632-520: The offspring generally disassociate from the mother and swim away, having been born with the instinctual abilities to protect and feed themselves. In a very small number of species, like the giant freshwater stingray ( Urogymnus polylepis ), the mother "cares" for her young by having them swim with her until they are one-third of her size. At the Sea Life London Aquarium , two female stingrays delivered seven baby stingrays, although

1680-749: The osteoderms of Borealosuchus , the crocodile that was an early clue to the mild Eocene climate of Western North America. Fish are common. The fossils of the herring-like Knightia , sometimes in dense layers, as if a school had wandered into anoxic water levels and were overcome, are familiar to fossil-lovers and are among the most commonly available fossils on the commercial market. There were two genera of indigenous freshwater stingray , Heliobatis and Asterotrygon . Approximately sixty vertebrate taxa in all have been found at Green River. Besides fishes they include at least eleven species of reptiles, and some birds and one armadillo -like mammal, Brachianodon westorum , with some scattered vertebrae of others, like

1728-437: The paternity of their offspring by refusing less qualified mates. Stingrays are ovoviviparous , bearing live young in "litters" of five to thirteen. During this period, the female's behavior transitions to support of her future offspring. Females hold the embryos in the womb without a placenta. Instead, the embryos absorb nutrients from a yolk sac and after the sac is depleted, the mother provides uterine "milk". After birth,

1776-463: The sand and hiding beneath it. Because their eyes are on top of their bodies and their mouths on the undersides, stingrays cannot see their prey after capture; instead, they use smell and electroreceptors ( ampullae of Lorenzini ) similar to those of sharks . Stingrays settle on the bottom while feeding, often leaving only their eyes and tails visible. Coral reefs are favorite feeding grounds and are usually shared with sharks during high tide. During

1824-449: The slightly drier mid-Eocene. The climate was moist and mild enough to support crocodiles , which do not tolerate frost, and the lakes were surrounded by sycamore ( e.g. Platanus wyomingensis ) forests. As the lake configurations shifted, each Green River location is distinct in character and time. The lake system formed over underlying river deltas and shifted in the flat landscape with slight tectonic movements, receiving sediments from

1872-459: The spinal blade or blades causes local trauma (from the cut itself), pain, swelling, muscle cramps from the venom and, later, may result in infection from bacteria or fungi. The injury is very painful, but rarely life-threatening unless the stinger pierces a vital area. The blade is often deeply barbed and usually breaks off in the wound. Surgery may be required to remove the fragments. Fatal stings are very rare. The death of Steve Irwin in 2006

1920-443: The spiracles, they can draw water free from sediment directly into their gills for gas exchange. These alternate ventilation organs are less efficient than the mouth, since spiracles are unable to pull the same volume of water. However, it is enough when the stingray is quietly waiting to ambush its prey. The flattened bodies of stingrays allow them to effectively conceal themselves in their environments. Stingrays do this by agitating

1968-754: The stingray's defensive reflex (use of its venomous stinger) may result in serious injury or death. The skin of the ray is used as an under layer for the cord or leather wrap (known as samegawa in Japanese ) on Japanese swords due to its hard, rough texture that keeps the braided wrap from sliding on the handle during use. Several ethnological sections in museums, such as the British Museum , display arrowheads and spearheads made of stingray stingers, used in Micronesia and elsewhere. Henry de Monfreid stated in his books that before World War II , in

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2016-465: The substrate, the ray will raise its head, generating a suction force that pulls the prey underneath the body. This form of whole-body suction is analogous to the buccal suction feeding performed by ray-finned fish. Stingrays exhibit a wide range of colors and patterns on their dorsal surface to help them camouflage with the sandy bottom. Some stingrays can even change color over the course of several days to adjust to new habitats. Since their mouths are on

2064-450: The superficial capillaries and cell death. Despite the number of cells and toxins that are within the stingray, there is little relative energy required to produce and store the venom. The venom is produced and stored in the secretory cells of the vertebral column at the mid-distal region. These secretory cells are housed within the ventrolateral grooves of the spine. The cells of both marine and freshwater stingrays are round and contain

2112-525: The underside of their bodies, they catch their prey, then crush and eat with their powerful jaws. Like its shark relatives, the stingray is outfitted with electrical sensors called ampullae of Lorenzini. Located around the stingray's mouth, these organs sense the natural electrical charges of potential prey. Many rays have jaw teeth to enable them to crush mollusks such as clams, oysters and mussels. Most stingrays feed primarily on mollusks , crustaceans and, occasionally, on small fish. Freshwater stingrays in

2160-632: The various sediments from the then active Absaroka Volcanic field to the north in the vicinity of Yellowstone and the San Juan volcanic field to the southeast provide dateable horizons within the sediments. The trona (hydrated sodium bicarbonate carbonate) beds of Sweetwater County, Wyoming are noted for a variety of rare evaporite minerals. The Green River Formation, is the type locality for eight rare minerals: bradleyite , ewaldite , loughlinite , mckelveyite-(Y) , norsethite , paralabuntsovite-Mg , shortite and wegscheiderite . It also has

2208-496: The venom penetrates the epidermis and mixes with the mucus to release the venom on its victim. Typically, other venomous organisms create and store their venom in a gland . The stingray is notable in that it stores its venom within tissue cells. The toxins that have been confirmed to be within the venom are cystatins , peroxiredoxin and galectin . Galectin induces cell death in its victims and cystatins inhibit defense enzymes. In humans, these toxins lead to increased blood flow in

2256-467: The world. Some species, such as the thorntail stingray ( Dasyatis thetidis ), are found in warmer temperate oceans and others, such as the deepwater stingray ( Plesiobatis daviesi ), are found in the deep ocean . The river stingrays and a number of whiptail stingrays (such as the Niger stingray ( Fontitrygon garouaensis )) are restricted to fresh water . Most myliobatoids are demersal (inhabiting

2304-498: Was only the second recorded in Australian waters since 1945. The stinger penetrated his thoracic wall and pierced his heart, causing massive trauma and bleeding. The venom of the stingray has been relatively unstudied due to the mixture of venomous tissue secretions cells and mucous membrane cell products that occurs upon secretion from the spinal blade. The spine is covered with the epidermal skin layer. During secretion,

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