50-609: 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
100-532: A clade of cartilaginous fishes , commonly known as rays , this taxon is also known as the superorder Batoidea , but the 5th edition of Fishes of the World classifies it as the division Batomorphi. They and their close relatives, the sharks , compose the subclass Elasmobranchii . Rays are the largest group of cartilaginous fishes, with well over 600 species in 26 families. Rays are distinguished by their flattened bodies, enlarged pectoral fins that are fused to
150-804: A 2011 study significantly reevaluated the phylogeny of batoids, using nuclear and mitochondrial DNA from 37 taxa , representing almost all recognized families and all of the traditional four major lineages. This is a far more numerous and diverse set of sample taxa than in any previous study, producing findings reflected in the cladogram below. Holocephali (incl. Chimaera ) [REDACTED] Selachimorpha (Sharks) [REDACTED] Rajiformes (Skates) [REDACTED] Platyrhinidae (Thornbacks) Torpediniformes (Electric rays) [REDACTED] "Guitarfishes 1" ( Trygonorrhinidae ) [REDACTED] "Guitarfishes 2" (incl. Pristidae (Sawfishes)) [REDACTED] Zanobatidae (Panrays) Myliobatoidei (Stingrays) [REDACTED] This study strongly confirmed
200-456: A 2021 study in Nature , the number of oceanic sharks and rays has declined globally by 71% over the preceding 50 years, jeopardising "the health of entire ocean ecosystems as well as food security for some of the world's poorest countries". Overfishing has increased the global extinction risk of these species to the point where three-quarters are now threatened with extinction. This is notably
250-399: A few species, like manta rays , live in the open sea, and only a few live in freshwater, while some batoids can live in brackish bays and estuaries. Most batoids have developed heavy, rounded teeth for crushing the shells of bottom-dwelling species such as snails , clams , oysters , crustaceans , and some fish , depending on the species. Manta rays feed on plankton . Batoids belong to
300-693: 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
350-403: A ventrally located mouth and can considerably protrude their upper jaw (palatoquadrate cartilage) away from the cranium to capture prey. The jaws have euhyostylic type suspension, which relies completely on the hyomandibular cartilages for support. Bottom-dwelling batoids breathe by taking water in through the spiracles, rather than through the mouth as most fish do, and passing it outward through
400-400: 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
450-405: A womb but without involvement of a placenta. The eggs of oviparous skates are laid in leathery egg cases that are commonly known as mermaid's purses and which often wash up empty on beaches in areas where skates are common. Capture-induced premature birth and abortion (collectively called capture-induced parturition) occurs frequently in sharks and rays when fished. Capture-induced parturition
500-532: 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
550-560: Is an extinct stingray genus in the monotypic family Dasyomyliobatidae , of the order Myliobatiformes . It contains a single species, D. thomyorkei , known from the Eocene Monte Bolca Lagerstätte of Italy. The specific epithet references the English musician and Radiohead vocalist Thom Yorke . The genus is characterized by a unique hybrid dentition and pectoral fin morphology that allowed
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#1732771942589600-633: 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
650-404: 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
700-833: 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 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
750-489: Is rarely considered in fisheries management despite being shown to occur in at least 12% of live bearing sharks and rays (88 species to date). Most species live on the sea floor, in a variety of geographical regions – mainly in coastal waters, although some live in deep waters to at least 3,000 metres (9,800 ft). Most batoids have a cosmopolitan distribution , preferring tropical and subtropical marine environments, although there are temperate and cold-water species. Only
800-732: 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
850-648: Is thought to represent a sister group to the Myliobatidae, and the two groups likely diverged during the Late Cretaceous . The Monte Bolca formation is thought to represent a shallow sea of the Tethys Ocean with scattered coral reefs and seagrass beds . With its combination of traits, Dasyomyliobatis may have been able to forage in both these shallow-water ecosystems as well as the open ocean. This article about prehistoric Batoidea
900-708: 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 the Eocene Monte Bolca formation from Italy , including
950-555: 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. Batoidea Batomorphi is
1000-537: The Jurassic . The oldest confirmed ray is Antiquaobatis , from the Pliensbachian of Germany . The clade is represented today by sharks , sawfish , rays and skates . Molecular evidence refutes the hypothesis that skates and rays are derived sharks. The monophyly of the skates , the stingrays , and the electric rays has long been generally accepted. Along with Rhinopristiformes , these comprise
1050-569: The Trygonorrhinidae , while the latter contains the remainder of Rhinopristiformes (the families Glaucostegidae , Pristidae , Rhinidae , and Rhinobatidae ). In addition, while traditional phylogenies often find electric rays to be the basalmost batoids, followed by the Rhinopristiformes, this analysis finds a polytomy between skates, electric rays, and thornbacks at the base of Batoidea, with weak support for skates being
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#17327719425891100-451: 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,
1150-501: 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
1200-578: 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
1250-519: 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
1300-472: The actual most basal lineage, followed by a clade uniting the electric rays and thornbacks. The Mesozoic Sclerorhynchoidea are basal or incertae sedis ; they show features of the Rajiformes but have snouts resembling those of sawfishes. However, evidence indicates they are probably the sister group to sawfishes. Eschmeyer's Catalog of Fishes classigies the rays as follows: According to
1350-595: The ancient lineage of cartilaginous fishes. Fossil denticles (tooth-like scales in the skin) resembling those of today's chondrichthyans date at least as far back as the Ordovician , with the oldest unambiguous fossils of cartilaginous fish dating from the middle Devonian . A clade within this diverse family, the Neoselachii , emerged by the Triassic , with the best-understood neoselachian fossils dating from
1400-678: The case in the Mediterranean Sea - most impacted by unregulated fishing - where a recent international survey of the Mediterranean Science Commission concluded that only 38 species of rays and skates still subsisted. All sharks and rays are cartilaginous fish, contrasting with bony fishes . Many rays are adapted for feeding on the bottom. Guitarfishes are somewhat between sharks and rays, displaying characteristics of both (though they are classified as rays). Dasyomyliobatis Dasyomyliobatis
1450-418: 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 the mandibular arch
1500-666: The four traditionally accepted major batoid lineages, as in Nelson's 2006 Fishes of the World . However, the exact phylogeny of the major batoid lineages, internally and with respect to one another, has been subject to diverse treatments. The following cladogram is based on a comprehensive morphological assessment of batoid phylogeny published in 2004: Holocephali (incl. Chimaera ) [REDACTED] Selachimorpha (Sharks) [REDACTED] Torpediniformes [REDACTED] Rhinopristiformes [REDACTED] Rajiformes [REDACTED] Myliobatiformes [REDACTED] However,
1550-507: The gills. Batoids reproduce in a number of ways. As is characteristic of elasmobranchs, batoids undergo internal fertilization . Internal fertilization is advantageous to batoids as it conserves sperm, does not expose eggs to consumption by predators, and ensures that all the energy involved in reproduction is retained and not lost to the environment. All skates and some rays are oviparous (egg laying) while other rays are ovoviviparous , meaning that they give birth to young which develop in
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1600-471: The head, and gill slits that are placed on their ventral surfaces. Batoids are flat-bodied, and, like sharks, are cartilaginous fish, meaning they have a boneless skeleton made of a tough, elastic cartilage. Most batoids have five ventral slot-like body openings called gill slits that lead from the gills , but the Hexatrygonidae have six. Batoid gill slits lie under the pectoral fins on
1650-409: 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
1700-805: 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
1750-562: 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,
1800-519: 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
1850-435: 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,
1900-461: 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
1950-441: The shift from undulatory to oscillatory swimming (and a resulting shift from a benthic to pelagic lifestyle), and to exploit a variety of prey from soft-bodied to hard-shelled organisms. As suggested by the genus name, it displays intermediate traits between the whiptail stingrays ( Dasyatidae ) and the eagle rays ( Myliobatidae ), and can thus be considered a transitional form in the origin of pelagic rays. Dasyomyliobatidae
2000-455: 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
2050-442: 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
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2100-750: 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
2150-465: 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
2200-449: 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
2250-419: The traditionally accepted internal monophyly of skates, stingrays, and electric rays. It also recovered panrays as sister to the stingrays, as older morphological analyses had suggested. However, it found the Rhinopristiformes, including the sawfishes and various "guitarfishes", to be paraphyletic , comprising two distinct clades. Referred to as "Guitarfishes 1" and "Guitarfishes 2", the former contains only
2300-525: 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
2350-401: The underside, whereas a shark's are on the sides of the head. Most batoids have a flat, disk-like body, with the exception of the guitarfishes and sawfishes , while most sharks have a spindle-shaped body. Many species of batoid have developed their pectoral fins into broad flat wing-like appendages. The anal fin is absent. The eyes and spiracles are located on top of the head. Batoids have
2400-495: 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
2450-467: 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
2500-496: 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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