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29-701: Mobula is a genus of rays in the family Mobulidae that is found worldwide in tropical and warm, temperate seas. Some authorities consider this to be a subfamily of the Myliobatidae (eagle rays). Their appearance is similar to that of manta rays , which are in the same family, and based on genetic and morphological evidence, the mantas belong in Mobula (they are traditionally in their own genus Manta ). Species of this genus are often collectively referred to as " devil rays ", " flying mobula ", or simply " flying rays ", due to their propensity for breaching , sometimes in

58-804: 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

87-452: 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

116-399: 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

145-405: A spectacular manner. These rays gather in groups and leap out of the surface into the air up to around two metres before splashing back into the water. Depending on the species, the devil rays can attain widths up to 1.1–5.2 m (3.6–17.1 ft), the largest being second only to the manta rays in size, which can reach 5.5–7.0 m (18.0–23.0 ft). Despite their size, little is known about

174-403: 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

203-405: 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

232-531: Is 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

261-414: Is no noticeable change in tonality. Most amphibians have external fertilization but there is an exception to some like salamanders which mostly have internal fertilization. Salamanders do not use intercourse for sexual reproduction due to their lack of external penis. Rather, the male salamander produces an encased capsule of sperm and nutrients called a spermatophore . The male deposits a spermatophore on

290-489: 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

319-525: 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

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348-553: 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

377-466: 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

406-578: 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

435-797: 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). Internal fertilization Most taxa that reproduce by internal fertilization are gonochoric . Male mammals , reptiles , and certain other vertebrates transfer sperm into

464-448: The devil rays, much of it anecdotal; the manta rays are better known. Most species entirely lack a tail stinger . In most species having a stinger, it is encased, rendering it harmless; only M. mobular has a "free" stinger. The genus was named by Constantine Samuel Rafinesque in 1810 describing the devil fish , Raia mobular or now Mobula mobular . The name can be explained from Latin mobilis "mobile" or "movable", because of

493-411: The egg and pick it up in her mouth. Then the males will encourage the female to open her mouth so they can fertilize the eggs while it is in the female's mouth. Internal fertilization in cartilaginous fishes contains the same evolutionary origin as reptiles, birds, and mammals that internally fertilize. Also in these internally fertilizing fish while the sperm is transferred to the reproductive tract there

522-599: The embryos are laid as eggs in oviparous organisms, or continue to develop inside the reproductive tract of the mother to be born later as live young in viviparous organisms. Internal fertilization evolved many times in animals . According to David B. Dusenbery all the features with internal fertilization were most likely a result from oogamy . It has been argued that internal fertilization evolve because of sexual selection through sperm competition . In amphibians , internal fertilization evolved from external fertilization . Fertilization which takes place inside

551-416: The female body is called internal fertilization in animals is done through the following different ways: At some point, the growing egg or offspring must be expelled. There are several possible modes of reproduction . These are traditionally classified as follows: Internal fertilization allows for: Some species of fish like guppies have the ability to internally fertilize, this process happens by

580-409: The female's vagina or cloaca through an intromittent organ during copulation . In most birds, the cloacal kiss is used, the two animals pressing their cloacas together while transferring sperm. Salamanders , spiders , some insects and some molluscs undertake internal fertilization by transferring a spermatophore , a bundle of sperm, from the male to the female. Following fertilization,

609-662: 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,

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638-507: 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

667-452: The ground and the female will pick it up with her cloaca (a combined urinary and genital opening) and fertilize her eggs with it. Over time amphibians have been found evolving to increasing internal fertilization. Within amphibians, it is common for high vertebrates to internally fertilize because of the transition from water to land during vertebrate evolution. There is an advantage for the amphibians who are internally fertilizing allowing for

696-464: 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

725-407: The male inserting a tubular fin into the female's reproductive opening and then will deposit sperm into her reproductive tract. There are other species of fish that are mouthbrooders which means that one fish puts the eggs in its mouth for incubation. A certain type of fish that is a mouthbrooder is called cichlids and many of them are maternal mouthbrooders. The process for this is the female would lay

754-498: The selection of a time and place for reproduction. Most birds do not have penises, but achieve internal fertilization via cloacal contact (or "cloaca kiss"). In these birds, males and females contact their cloacas together, typically briefly, and transfer sperm to the female. However, water fowls such as ducks and geese have penises and are able to use them for internal fertilization. While birds have internal fertilization, most species no longer have phallus structures. This makes them

783-468: The species' migratory habits; another explanation is that mobula is a local name used by people living in Azores who call this creature there. Based on genetics and, to a lesser degree, morphological evidence, the genus was redefined in 2017. Under this arrangement, Manta is included in Mobula . FishBase recognizes 11 species: Extinct species by Shark-References: Batoidea Batomorphi

812-419: 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

841-401: 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

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