Pale-edged stingray | |
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Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Chondrichthyes |
Superorder: | Batoidea |
Order: | Myliobatiformes |
Family: | Dasyatidae |
Genus: | Telatrygon |
Species: | T. zugei |
Binomial name | |
Telatrygon zugei (J. P. Müller & Henle, 1841) | |
Synonyms | |
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The pale-edged stingray or sharpnose stingray (Telatrygon zugei) is a species of stingray in the family Dasyatidae, found in the Indian and Pacific Oceans from India to the western Malay Archipelago and southern Japan. This bottom-dwelling ray is most commonly found over sandy areas shallower than 100 m (330 ft), as well as in estuaries. Measuring up to 29 cm (11 in) across, the pale-edged stingray has a diamond-shaped pectoral fin disc, a long projecting snout, small eyes, and a whip-like tail with both dorsal and ventral fin folds. It is chocolate brown above and white below.
The diet of the pale-edged stingray consists mainly of small crustaceans and fishes. Reproduction is aplacental viviparous, with females bearing litters of 1–3 young. Caught as bycatch and utilized for its meat, this species is threatened by heavy fishing pressure throughout its range and has been assessed as Vulnerable by the International Union for Conservation of Nature (IUCN).
German biologists Johannes Müller and Friedrich Henle originally described the pale-edged stingray from seven syntypes, in their 1841 Systematische Beschreibung der Plagiostomen. They named it Trygon zugei after zugu-ei, the Japanese name for this species. The genus Trygon was synonymized with Dasyatis by subsequent authors. [2] Several early accounts of D. zugei were confounded by specimens of D. acutirostra ; in 1988 Nishida and Nakaya published a study that resolved the differences between these two species and designated a new lectotype for D. zugei. [3]
Lisa Rosenberger's 2001 phylogenetic analysis, based on morphological characters, found that the pale-edged stingray is sister to a clade containing the whitespotted whipray (Maculabatis gerrardi), the pearl stingray (Fontitrygon margaritella), and the smooth butterfly ray (Gymnura micrura). These results support the growing consensus that neither Dasyatis nor Himantura are monophyletic. [4]
The range of the pale-edged stingray extends from the Indian subcontinent eastward to Java and Borneo, and northward to the Philippines and southern Japan. [5] This species inhabits the inner continental shelf, favoring sandy flats in water under 100 m (330 ft) deep, and also frequently enters estuaries. [1] [6]
The pale-edged stingray has a diamond-shaped pectoral fin disc slightly longer than wide, with concave anterior margins merging into an elongated, triangular snout; the head comprises more than half of the disc length. The eyes are small, with a pair of much larger spiracles immediately behind. There is a nearly rectangular curtain of skin between the nares, with a fringed rear margin. The mouth is gently curved, without papillae on the floor. There are 40–55 tooth rows in either jaw, arranged with a quincunx pattern into pavement-like surfaces. The teeth of adult males have pointed cusps while those of juveniles and females are blunt. [3] [7]
The pelvic fins are triangular. The tail is whip-like, much longer than the disc, and bears a stinging spine. A low dorsal fin fold originates just posterior of the spine tip while a deeper ventral fin fold originates below the spine base. Young individuals have smooth skin, while adults have a row of 5–9 small tubercles in front of the spine. The dorsal surface is a uniform chocolate brown, darkening on the tail fin folds, while the underside is white with a brown band around the margin of the disc. [3] This species reaches a length of 75 cm (30 in) and width of 29 cm (11 in), though most do not exceed 18–24 cm (7.1–9.4 in) in width. [1] [5] The pale-edged stingray differs from the similar but larger D. acutirostra in having smaller eyes and an upper tail fin fold, as well as in several meristic counts such as the number of intestinal valves. [3]
The pale-edged stingray feeds mainly on bottom-dwelling crustaceans, in particular prawns, but also takes small fishes. [1] [6] Parasites that have been identified from this species include the tapeworms Acanthobothrium zugeinensis, [8] Balanobothrium yamagutii, [9] Pithophorus zugeii, [10] Polypocephalus ratnagiriensis and P. visakhapatnamensis, [11] [12] Rhinebothrium xiamenensis, [13] Shindeiobothrium karbharae, [14] Tetragonocephalum raoi, [15] Tylocephalum singhii, [16] and Uncibilocularis indiana and U. veravalensis, [17] [18] and the capsalid monogenean Trimusculotrema schwartzi. [19] Like other stingrays, the pale-edged stingray is aplacental viviparous, with the young sustained initially by yolk and later histotroph ("uterine milk") secreted by the mother. Females give birth to 1–3 young at a time; there is no defined reproductive seasonality, at least in Indonesian waters. Newborns measure 8–10 cm (3.1–3.9 in) across. Males mature sexually at a disc width of 18 cm (7.1 in) and females at a disc width of 19 cm (7.5 in). [1]
Large numbers of pale-edged stingrays are caught incidentally in bottom trawls and trammel nets, particularly in the Gulf of Thailand, the Java Sea, and off the Indian coast. Most individuals landed are retained for human consumption, although the small size of this species limits its economic significance. [1] [6] The IUCN has assessed the pale-edged stingray as near threatened and notes that it is vulnerable. Across most of its range, this species experiences heavy and increasing fishing pressure, with all size classes susceptible to capture. [1]
The longtail stingray, is a species of stingray in the family Dasyatidae, found in the eastern Pacific Ocean from Baja California to Colombia. It inhabits sandy habitats down to a depth of 90 m (300 ft). Measuring up to 1.56 m (5.1 ft) across, this species has a rhomboid pectoral fin disc, a lower fin fold on the tail, and numerous dermal denticles along the back and behind the stinging spine. The longtail stingray feeds mainly on bottom-dwelling bony fishes and crustaceans. It is aplacental viviparous, with females giving birth to 1–5 young in late summer. It is caught for food, likely throughout its range, but specific fishery data is lacking.
The bluespotted ribbontail ray 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.
The giant freshwater stingray is a species of stingray in the family Dasyatidae. It is found in large rivers and estuaries in Southeast Asia and Borneo, though historically it may have been more widely distributed in South and Southeast Asia. The largest freshwater fish and the largest stingray in the world, this species grows up to 2.2 m (7.2 ft) across and can reach up to 300 kg (660 lb) in weight. It has a relatively thin, oval pectoral fin disc that is widest anteriorly, and a sharply pointed snout with a protruding tip. Its tail is thin and whip-like, and lacks fin folds. This species is uniformly grayish brown above and white below; the underside of the pectoral and pelvic fins bear distinctive wide, dark bands on their posterior margins.
The pelagic stingray is a species of stingray in the family Dasyatidae, and the sole member of its genus. It is characterized by the wedge-like shape of its pectoral fin disc, which is much wider than long, as well as by the pointed teeth in both sexes, whip-like tail with extremely long tail spine, and uniform violet to blue-green coloration. It generally reaches 59 cm (23 in) in width. The pelagic stingray has a worldwide distribution in waters warmer than 19 °C (66 °F), and migrates seasonally to spend the summer closer to the continental shelf and at higher latitudes. The only stingray that almost exclusively inhabits the open ocean, this species is typically found in surface waters down to a depth of 100 m (330 ft). As a consequence of its midwater habits, its swimming style has evolved to feature more of a flapping motion of the pectoral fins, as opposed to the disc margin undulations used by other, bottom-dwelling stingrays.
The sharpnose stingray is a little-known species of stingray in the family Dasyatidae, found off southern Japan and in the East China Sea. With a rounded pectoral fin disc and a long, projecting snout, T. acutirostra resembles the smaller pale-edged stingray. A number of characteristics differentiate this species from T. zugei, including larger eyes and the absence of a dorsal fin fold on the tail. The International Union for Conservation of Nature (IUCN) has assessed this species as Near Threatened, as its restricted distribution renders it vulnerable to increases in fishing pressure.
The red stingray is a species of stingray in the family Dasyatidae, found in the northwestern Pacific Ocean off Japan, Korea, and China, and possibly elsewhere. It primarily inhabits shallow, sandy habitats close to shore, and has been known to enter brackish water. The red stingray has a diamond-shaped pectoral fin disc and gains its common name from its bright orange-red underside; there may also be patches of orange at various spots on its upper surface. Most individuals are no more than 1 m (3.3 ft) long.
The plain maskray or brown stingray, is a species of stingray in the family Dasyatidae. It is found in shallow, soft-bottomed habitats off northern Australia. Reaching 24 cm (9.4 in) in width, this species has a diamond-shaped, grayish green pectoral fin disc. Its short, whip-like tail has alternating black and white bands with fin folds above and below. There are short rows of thorns on the back and the base of the tail, but otherwise the skin is smooth. While this species possesses the dark mask-like pattern across its eyes common to its genus, it is not ornately patterned like other maskrays.
The diamond stingray is a species of stingray in the family Dasyatidae. It is found in the coastal waters of the eastern Pacific Ocean from southern California to northern Chile, and around the Galápagos and Hawaiian Islands. This bottom-dweller generally inhabits sandy or muddy flats near rocky reefs and kelp forests, to a depth of 30 m (98 ft), though off Hawaii it may range considerably deeper. As its common name suggests, this species has an angular, diamond-shaped pectoral fin disc that is plain brown or gray above, with rows of tubercles along the midline and on the "shoulders". The long, whip-like tail has both dorsal and ventral fin folds, which distinguish this ray from the closely similar longtail stingray (D. longa). It typically grows to 1 m (3.3 ft) across.
The estuary stingray, also called the estuary stingaree or brown stingray, is a species of stingray in the family Dasyatidae. Endemic to eastern Australia, it typically inhabits shallow, mangrove-lined tidal rivers, estuaries, and bays in southern Queensland and New South Wales. This yellow-brown to olive ray grows to at least 93 cm (37 in) across. It has a diamond-shaped pectoral fin disc and a mostly smooth, whip-like tail bearing both dorsal and ventral fin folds. It can additionally be identified by its long, narrow nostrils and the row of thorns along the midline of its back.
The sharpsnout stingray or wingfin stingray is a species of stingray in the family Dasyatidae, found from off Venezuela to northern Brazil. It inhabits shallow, brackish water, shifting towards the coast in the dry season and away from it in the rainy season. Typically measuring 70 cm (28 in) across, this dark brown ray is easily identifiable by its long, projecting snout and elongated, acutely pointed pelvic fins. Its diet consists of bottom-dwelling invertebrates. Reproduction is aplacental viviparous, with females bearing one to three pups annually. Naturally uncommon and slow-reproducing, the sharpnose stingray is under pressure by both artisanal and commercial fisheries, leading the International Union for Conservation of Nature (IUCN) to assess it as critically endangered.
The longnose stingray is a species of stingray in the family Dasyatidae, native to the western Atlantic Ocean from the southern Gulf of Mexico to Brazil. Found in coastal waters no deeper than 36 m (118 ft), this demersal species favors muddy or sandy habitats. The longnose stingray is characterized by its angular, rhomboid pectoral fin disc, moderately projecting snout, and whip-like tail with a dorsal keel and ventral fin fold. It typically grows to 1.25 m (4.1 ft) across and is brownish above and light-colored below.
The common stingray is a species of stingray in the family Dasyatidae, found in the northeastern Atlantic Ocean and the Mediterranean and Black Seas. It typically inhabits sandy or muddy habitats in coastal waters shallower than 60 m (200 ft), often burying itself in sediment. Usually measuring 45 cm (18 in) across, the common stingray has a diamond-shaped pectoral fin disc slightly wider than long, and a whip-like tail with upper and lower fin folds. It can be identified by its plain coloration and mostly smooth skin, except for a row of tubercles along the midline of the back in the largest individuals.
The roughtail stingray is a species of stingray in the family Dasyatidae, with separate populations in coastal waters of the northwestern, eastern, and southwestern Atlantic Ocean. This bottom-dwelling species typically inhabits sandy or muddy areas with patches of invertebrate cover, at a depth of 15–50 m (49–164 ft). It is seasonally migratory, overwintering in offshore waters and moving into coastal habitats for summer. The largest whip-tail stingray in the Atlantic, the roughtail stingray grows up to 2.6 m (8.5 ft) across and 360 kg (800 lb) in weight. It is plain in color, with an angular, diamond-shaped pectoral fin disc and a long, whip-like tail bearing a subtle fin fold underneath. The many thorns on its back and tail serve to distinguish it from other stingrays that share its range.
The giant stumptail stingray, Dasyatis gigantea, is a species of stingray in the family Dasyatidae, known from only two specimens collected from the Peter the Great Bay in the Sea of Japan. This large species is characterized by rhomboid pectoral fin disc wider than long, a relatively long snout, and a short, blunt tail. The International Union for Conservation of Nature (IUCN) has listed this species as Data Deficient and recommended further study.
The blackish stingray, Hemitrygon navarrae, is a little-known species of stingray in the family Dasyatidae, found in the northwestern Pacific Ocean off the coasts of mainland China and Taiwan. This species reaches 38 cm (15 in) across and has a chocolate brown, diamond-shaped pectoral fin disc nearly as long as wide. Its whip-like tail bears three large tubercles in front of the stinging spine, as well as both dorsal and ventral fin folds with the ventral fold half as long as the disc. Caught as bycatch in bottom trawls, the blackish stingray is frequently marketed as food in China. T
The Chinese stingray, Hemitrygon sinensis, is a little-known species of stingray in the family Dasyatidae, found in the northwestern Pacific Ocean off the coasts of China and Korea. This species is characterized by a band of small dermal denticles running along the upper surface of its diamond-shaped pectoral fin disc, from the snout to the tail spine. It can grow to 40 cm (16 in) across and 82 cm (32 in) long. The Chinese stingray is taken incidentally in bottom trawls and is one of the three most commonly marketed stingrays in China. At present, the International Union for Conservation of Nature (IUCN) has assessed its conservation status as endangered.
The pitted stingray is a species of stingray in the family Dasyatidae, endemic to the waters around Japan and the Sea of Japan. It typically found near the coast at depths of 40–60 m (130–200 ft), but may also venture into the open sea. Measuring up to 2 m (6.6 ft) across, the pitted stingray has a diamond-shaped pectoral fin disc with a characteristic "W"-shaped groove on the underside. The total length including the tail has a record of 2.8 m (9.2 ft). Other identifying characteristics of this species include its dark gray dorsal coloration with small white spots, and the presence of dorsal tubercles in adults. Pitted stingrays are caught as bycatch in coastal fisheries and brought to market. The International Union for Conservation of Nature (IUCN) does not yet have sufficient data to assess this species beyond Data Deficient. Some authors regard this species as the same as the Short-tail stingray.
The Bennett's stingray or frilltailed stingray is a little-known species of stingray in the family Dasyatidae, with a wide but ill-defined distribution in the Indian and Pacific Oceans. This species is characterized by a rhomboid, yellow-brown pectoral fin disc with a fairly long snout, and an extremely long tail with a correspondingly long ventral fin fold. It measures up to 50 cm (20 in) across. It feeds on fish, and is aplacental viviparous. It is likely caught by demersal fisheries.
Acanthobothrium bullardi is a species of parasitic onchobothriid tapeworm first found in the whiptail stingray, Dasyatis brevis, in the Gulf of California. This species of parasitic tapeworm was originally discovered alongside four other varieties of tapeworms in the Gulf of California during a survey of the area that was done in the years 1993 as well as 1996. Information on this discovery can be found in greater detail in the article written by Sohini Ghoshroy and J.N. Caira titled "Four New Species of Acanthobothrium from the Whiptail Stingray Dasyatis Brevis in the Gulf of California, Mexico". This article claims itself as the first document with record on these tapeworms in California. Although this particular variety has only been discovered on the bodies of whiptail stingray, other Acanthobothrium species have been found on the bodies of many more animals including sharks. This is described in the article written by Caroline Fyler titled "Systematics, biogeography and character evolution in the tapeworm genus Acanthobothrium van Beneden, 1850 ".
Acanthobothrium dasi is a species of parasitic onchobothriid tapeworms first found in the whiptail stingray, Dasyatis brevis, in the Gulf of California. It is relatively small, possesses few segments, relatively few testes, and shows asymmetrical ovaries. It also differs from its cogenerate species by its hook size and length of its hook prongs; cirrus sac size; the position of its genital pore, the number of testes columns that are anterior to the cirrus sac; as well as a number of postvaginal testes.