The most dangerous predator to blue-spotted stingrays are human beings. Blue-spotted stingrays are a popular ray to have in aquarium tanks. However, Taeniura lymma is very hard to take care of in an at-home aquarium. Besides humans, the only other type of predator known to this species of stingrays is the hammerhead shark. The hammerhead shark uses the cartilaginous projections form the side of their heads to pin them down to the bottom of the substrate while taking bites from the stingray's disc. The hammerhead is able to avoid being stung by the poisonous spines on the rays tail by pinning the stingray down.
Known Predators:
Taeniura lymma is a colorful stingray with distinct, large, bright blue spots on its oval, elongated body. The snout is rounded and angular with broad outer corners. The tail tapers and can be equal to or slightly less than the body length when intact. Its caudal fin is broad and reaches to the tip of the tail. At the tip of the tail are two sharp venomous spines which permit this ray to strike at enemies forward of its head. The tail of Taeniura lymma can be easily recognized by the blue side-stripes found on either side. It has large spiracles that lie very close to its large eyes. It can grow to a disc diameter of about 25 cm but has been reported as being as large as 95 cm in diameter. The mouth is found on the underside of the body along with the gills. Within the mouth are two plates, which are used for crushing the shells of crabs, prawns, and mollusks.
Range length: 95 (high) cm.
Average length: 25 cm.
Other Physical Features: ectothermic ; bilateral symmetry ; venomous
The lifespan of Taeniura lymma is still unknown.
Taeniura lymma is found on sandy bottoms around coral reefs. These rays like to bury themselves just underneath the sand where they will feed on various invertebrates. They usually are found on shallow continental shelves; however, they have also been observed around coral rubble and shipwreck debris at depths of 20-25m deep. Divers and snokelers will often detect this ray by its distinctive ribbon-like tail poking out from a crack in the coral. These rays are most abundant inshore.
Range depth: 25 (high) m.
Habitat Regions: tropical ; saltwater or marine
Aquatic Biomes: benthic ; reef
The body of Taeniura lymma is made completely out of cartilage and contains no bone whatsoever. The stinging barbs on its tail can be regenerated if broken off. One interesting fact about the venom that is contained within the stinging barbs is that it can be broken down by heat. Therefore, if you ever encounter one of these magnificent animals and happen to get stung, immediately soak the wound in hot water in order to break down the venom and reduce the pain. Another interesting fact about Taeniura lymma is that it is one of the few species of rays that can retain their urine.
Taeniura lymma uses electroreception to communicate with other members of its species. Blue-spotted stingrays,use strucutres called the ampullae of Lorenzini, which allow them to detect slight electrical impulses within the water. This electroreception is often used as a means of recognizing members of the same species.
Communication Channels: chemical ; electric
Perception Channels: visual ; tactile ; chemical ; electric
Although this species is very wide ranging and common, it is subject to human-induced problems because of capture by inshore fisheries and its attractiveness for the marine aquarium fish trade. Another major threat to this species is the destruction of its coral reef habitat. Without a habitat in which to live, this species may be pushed to extinction along with other species of the coral reef habitat.
US Migratory Bird Act: no special status
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: near threatened
When blue-spotted stingrays are born, they hatch out of egg cases and are pale gray or brown and are spotted with black or rusty red and white. These patterns and markings are distinct to each individual within a litter. As adults, they are olive-gray or gray-brown to yellow dorsally and white ventrally with numerous blue spots. When born, the young stingrays are about nine cm long and can grow to around 25cm as adults. The young are born out of egg cases with a soft tail that is encases in a thin layer of skin to prevent injury to the mother during birth. The skin is eventually lost and the tail is used as a protective mechanism.
The sting that of blue-spotted stingrays may be very painful.
Negative Impacts: injures humans (bites or stings)
Taeniura lymma is a popular aquarium pet. Their beautiful coloration makes them a prime candidate for an aquarium pet. In Australia, Taeniura lymma is often eaten and hunted for its meat.
Positive Impacts: pet trade
Taeniura lymma plays an important role in their ecosystem. Taeniura lymma is a secondary consumer. It feeds on nekton such as bony fish. It also feeds on zoobenthos organisms including benthic crustaceans like crabs, shrimp/prawns, and worms such as polychaetes.
Taeniura lymma has very distinct feeding behaviors. During high tide, it migrates in groups into shallow sandy areas of tidal flats to feed on sand worms, shrimps, hermit crabs, and small fishes. At low tide it recedes back into the ocean, usually alone to hide in the coral crevices of the reef.
Blue-spotted stingrays will feed on many things such as bony fish, crabs, shrimp, polychaetes and other benthic invertebrates. Since the mouth is located on the underside of the body, food is trapped by pressing the prey into the substrate with their discs. The food is then directed into the mouth by maneuvering the disc over the prey.
Taeniura lymma can detect its prey through an electroreceptor system. The nostrils are partly covered with a broad fleshy lobe, known as the internasal flap. This is covered in sensory pores and extends to the mouth. These pores form part of the ampullae of Lorenzini (the electrorecption system.) This electroreceptor system can detect electrical fields produced by the prey. This electroreceptor system cannot only be used to detect prey but can also be used to detect predators and other members of the same species.
Animal Foods: fish; aquatic or marine worms; aquatic crustaceans; other marine invertebrates
Primary Diet: carnivore (Piscivore , Eats non-insect arthropods)
Taeniura lymma, commonly known as blue-spotted stingrays, is found primarily in the Indo-west Pacific. They may be found in shallow continental shelf waters ranging from temperate to tropical seas. They prefer areas with sandy or sedimentary substrates in which they bury themselves. Sightings of Taeniura lymma have been recorded in Australia in shallow tropical marine waters from Ningaloo Reef, Western Australia to Bundaberg, Queensland. They can be found at depths of up to 25 m and have also been recorded to range in location from southern Africa and the Red Sea to the Solomon Islands.
Biogeographic Regions: australian (Native ); indian ocean (Native ); pacific ocean (Native )
Taeniura lymma is ovoviviparous. This means that the embryo is nourished by the yolk and the eggs are retained within the female until they hatch. The ray produces about seven live young in every litter. Each juvenile is born with the distinctive blue markings of its parents in miniature. In courtship, the male often follows the female with his acutely sensitive nose close to her cloaca in search of a chemical signal that the female will emit. Courtship usually includes some sort of nibbling or biting of the disc. The teeth of the male are used to hold the female in place during population. The male fertilizes the female via internal fertilization through the use of their claspers. The breeding season is usually in late spring through the summer and gestation can be anywhere from 4 months to a year.
Because only about seven live young are produced in each litter, this species is highly vulnerable to population collapses from overfishing, habitat loss and the pet trade. They also have a long gestation period making them even more susceptible to population collapse.
Breeding season: late spring throught summer
Average number of offspring: 7.
Range gestation period: 4 to 12 months.
Key Reproductive Features: iteroparous ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (Internal ); ovoviviparous
The bluespotted ribbontail ray (Taeniura lymma) is a species of stingray in the family Dasyatidae. Found from the intertidal zone to a depth of 30 m (100 ft), this species is common throughout the tropical Indian and western Pacific Oceans in nearshore, coral reef-associated habitats. It is a fairly small ray, not exceeding 35 cm (14 in) in width, with a mostly smooth, oval pectoral fin disc, large protruding eyes, and a relatively short and thick tail with a deep fin fold underneath. It can be easily identified by its striking color pattern of many electric blue spots on a yellowish background, with a pair of blue stripes on the tail.
At night, small groups of bluespotted ribbontail rays follow the rising tide onto sandy flats to root for small benthic invertebrates and bony fishes in the sediment. When the tide recedes, the rays separate and withdraw to shelters on the reef. Reproduction is aplacental viviparous, with females giving birth to litters of up to seven young. This ray is capable of injuring humans with its venomous tail spines, though it prefers to flee if threatened. Because of its beauty and size, the bluespotted ribbontail ray is popular with private aquarists despite being poorly suited to captivity.
The bluespotted ribbontail ray was originally described as Raja lymma by Swedish naturalist Peter Forsskål, in his 1775 Descriptiones Animalium quae in itinere ad maris australis terras per annos 1772, 1773, et 1774 suscepto collegit, observavit, et delineavit Joannes Reinlioldus Forster, etc., curante Henrico Lichtenstein.[2] The specific epithet lymma means "dirt".[3] Forsskål did not designate a type specimen.[2] In 1837, German biologists Johannes Peter Müller and Friedrich Gustav Jakob Henle created the genus Taeniura for Trygon ornatus, now known to be a junior synonym of this species.[4][5]
Other common names used for this species include bluespotted ray, bluespotted fantail ray, bluespotted lagoon ray, bluespotted stingray, fantail ray, lesser fantail ray, lagoon ray, reef ray, ribbon-tailed stingray, and ribbontail stingray.[5] Morphological examination has suggested that the bluespotted ribbontail ray is more closely related to the amphi-American Himantura (H. pacifica and H. schmardae) and the river stingrays (Potamotrygonidae) than to the congeneric blotched fantail ray (T. meyeni), which is closer to Dasyatis and Indo-Pacific Himantura.[6]
Widespread in the nearshore waters of the tropical Indo-Pacific region, the bluespotted ribbontail ray has a range that extends around the periphery of the Indian Ocean from South Africa to the Arabian Peninsula to Southeast Asia, including Madagascar, Mauritius, Zanzibar, the Seychelles, Sri Lanka, and the Maldives. It is rare in the Persian Gulf and Gulf of Oman.[1][7] In the Pacific Ocean, this species is found from the Philippines to northern Australia, as well as around numerous Melanesian and Polynesian islands as far east as the Solomon Islands.[1] Rarely found deeper than 30 m (100 ft), the bluespotted ribbontail ray is a bottom-dwelling species that frequents coral reefs and adjacent sandy flats. It is also commonly encountered in the intertidal zone and tidal pools, and has been sighted near seagrass beds.[1][8] Every summer, considerable numbers of bluespotted ribbontail rays arrive off South Africa.[3]
The pectoral fin disc of the bluespotted ribbontail ray is oval in shape, around four-fifths as wide as long, with a rounded to broadly angular snout. The large, protruding eyes are immediately followed by the broad spiracles. There is a narrow flap of skin between the nares with a fringed posterior margin, reaching past the mouth. The lower jaw dips at the middle and deep furrows are present at the mouth corners. There are 15–24 tooth rows in either jaw, arranged into pavement-like plates, and two large papillae on the floor of the mouth.[3][9] The pelvic fins are narrow and angular. The thick, depressed tail measures about 1.5 times the disc length and bears one or two (usually two) serrated spines well behind the tail base; there is a deep fin fold on the ventral surface, reaching the tip of the tail, and a low midline ridge on the upper surface.[7][9]
The skin is generally smooth, save for perhaps a scattering of small thorns on the middle of the back.[9] The dorsal coloration is striking, consisting of numerous circular, neon blue spots on a yellowish brown or green background; the spots vary in size, becoming smaller and denser towards the disc margin. The tail has two stripes of the same blue running along each side as far as the spines. The eyes are bright yellow and the belly is white.[3][8] Individuals found off southern Africa may lack the blue tail stripes.[10] The bluespotted ribbontail ray grows to 35 cm (14 in) across, 80 cm (31 in) long, and 5 kg (11 lb).[5][11]
One of the most abundant stingrays inhabiting Indo-Pacific reefs, the bluespotted ribbontail ray generally spends the day hidden alone inside caves or under coral ledges or other debris (including from shipwrecks), often with only its tail showing.[8][9][12] At night, small groups assemble and swim onto shallow sandy flats with the rising tide to feed. Unlike many other stingrays, this species seldom buries itself in sand.[13] The bluespotted ribbontail ray excavates sand pits in search of molluscs, polychaete worms, shrimps, crabs, and small benthic bony fishes; when prey is located, it is trapped by the body of the ray and maneuvered into the mouth with the disc. Other fishes, such as goatfish, frequently follow foraging rays, seeking food missed by the ray.[10][14]
Breeding in the bluespotted ribbontail ray occurs from late spring to summer; the male follows the female and nips at her disc, eventually biting and holding onto her for copulation.[14] There is also a documented instance of a male holding onto the disc of a smaller male bluespotted stingray (Dasyatis kuhlii), in a possible case of mistaken identity. Adult males have been observed gathering in shallow water, which may relate to reproduction.[12]: 88 Like other stingrays, this species is aplacental viviparous: the embryos are initially sustained by yolk, which later in development is supplemented by histotroph ("uterine milk", containing mucus, fat, and proteins) produced by the mother. The gestation period is uncertain, but is thought to be between four and twelve months long. Females bear litters of up to seven young, each a miniature version of the adult measuring around 13–14 cm (5.1–5.5 in) across.[13][15] Males attain sexual maturity at a disc width of 20–21 cm (7.9–8.3 in); the maturation size of females is unknown.[5][15]
Known predators of the bluespotted ribbontail ray include hammerhead sharks (Sphyrna) and bottlenose dolphins (Tursiops); it is also potentially preyed upon by other large fishes and marine mammals.[13][16] When threatened, this ray tends to flee at high speed in a zigzag pattern, to throw off pursuers.[8] Numerous parasites have been identified from this species: the tapeworms Aberrapex manjajiae,[17] Anthobothrium taeniuri,[18] Cephalobothrium taeniurai,[19] Echinobothrium elegans and E. helmymohamedi,[20][21] Kotorelliella jonesi,[22] Polypocephalus saoudi,[23] and Rhinebothrium ghardaguensis and R. taeniuri,[24] the monogeneans Decacotyle lymmae,[25] Empruthotrema quindecima,[26] Entobdella australis,[27] and Pseudohexabothrium taeniurae,[28] the flatworms Pedunculacetabulum ghardaguensis and Anaporrhutum albidum,[29][30] the nematode Mawsonascaris australis,[31] the copepod Sheina orri,[32] and the protozoan Trypanosoma taeniurae.[33] This ray has been observed soliciting cleanings from the bluestreak cleaner wrasse (Labroides dimidiatus) by raising the margins of its disc and pelvic fins.[12]
While timid and innocuous towards humans, the bluespotted ribbontail ray is capable of inflicting an excruciating wound with its venomous tail spines.[13] Its attractive appearance and relatively small size has resulted in its being the most common stingray found in the home aquarium trade.[34] It seldom fares well in captivity and few hobbyists are able to maintain one for long.[12] Many specimens refuse to feed in the aquarium, and seemingly healthy individuals often inexplicably die or stop feeding.[12] A higher degree of success has been achieved by public aquariums and a breeding project is maintained by the European Association of Zoos and Aquaria (for example, a total of 15 pups were born at Lisbon Oceanarium from 2011 to 2013).[35] The bluespotted ribbontail ray is utilized as food in East Africa, Southeast Asia, and Australia; it is captured intentionally or incidentally using gillnets, longlines, spears, and fence traps.[1][15]
The International Union for Conservation of Nature (IUCN) has assessed the bluespotted ribbontail ray as Least Concern. Although relatively common and widely distributed, this species faces continuing degradation of its coral reef habitat throughout its range, from development and destructive fishing practices using cyanide or dynamite. Its populations are under heavy pressure by artisanal and commercial fisheries, and by local collecting for the aquarium trade.[1]
{{cite journal}}: CS1 maint: multiple names: authors list (link) The bluespotted ribbontail ray (Taeniura lymma) is a species of stingray in the family Dasyatidae. Found from the intertidal zone to a depth of 30 m (100 ft), this species is common throughout the tropical Indian and western Pacific Oceans in nearshore, coral reef-associated habitats. It is a fairly small ray, not exceeding 35 cm (14 in) in width, with a mostly smooth, oval pectoral fin disc, large protruding eyes, and a relatively short and thick tail with a deep fin fold underneath. It can be easily identified by its striking color pattern of many electric blue spots on a yellowish background, with a pair of blue stripes on the tail.
At night, small groups of bluespotted ribbontail rays follow the rising tide onto sandy flats to root for small benthic invertebrates and bony fishes in the sediment. When the tide recedes, the rays separate and withdraw to shelters on the reef. Reproduction is aplacental viviparous, with females giving birth to litters of up to seven young. This ray is capable of injuring humans with its venomous tail spines, though it prefers to flee if threatened. Because of its beauty and size, the bluespotted ribbontail ray is popular with private aquarists despite being poorly suited to captivity.
