Der Tiefwasser-Stachelrochen (Plesiobatis daviesi) ist eine Rochenart aus der Ordnung Myliobatiformes. Er ist die einzige Art der monotypischen Familie Plesiobatidae.
Der Lebensbereich der Tiefwasser-Stachelrochen befindet sich in einer Tiefe von 44 bis 680 m. Man findet sie über weichem Untergrund, wo sie sich von kleinen Fischen, Krabben, Garnelen und Langusten sowie Tintenfischen und polychaeten Würmern ernähren.
Ihr Verbreitungsgebiet ist der Indische Ozean zwischen der südostafrikanischen Küste (Südafrika und Mosambik) und Südindien sowie der Pazifische Ozean zwischen Indien im Westen und den Philippinen im Osten, zwischen Japan im Norden und Australien im Süden. Im Jahre 2003 wurden bei einer Expedition zur Erforschung untermeerischer Canyons vor Hawaii auch Exemplare von Plesiobatis daviesi in einer Tiefe von 650 m beobachtet. Bevorzugt werden also die Meere im indo-pazifischen Raum zwischen 33° nördlicher Breite und 33° südlicher Breite.
Wegen seiner Lebensweise in tiefen und schwer zugänglichen Zonen des Kontinentalschelfs ist die Lebensweise des Tiefwasser-Stachelrochens noch wenig erforscht. Künftige Tiefwasserexpeditionen werden in diesen Lebensräumen noch viele bisher unbeschriebene Lebewesen entdecken, darunter vielleicht auch weitere Arten der Familie der Tiefwasser-Stachelrochen.
Der Tiefwasser-Stachelrochen (Plesiobatis daviesi) ist eine Rochenart aus der Ordnung Myliobatiformes. Er ist die einzige Art der monotypischen Familie Plesiobatidae.
Der Lebensbereich der Tiefwasser-Stachelrochen befindet sich in einer Tiefe von 44 bis 680 m. Man findet sie über weichem Untergrund, wo sie sich von kleinen Fischen, Krabben, Garnelen und Langusten sowie Tintenfischen und polychaeten Würmern ernähren.
Ihr Verbreitungsgebiet ist der Indische Ozean zwischen der südostafrikanischen Küste (Südafrika und Mosambik) und Südindien sowie der Pazifische Ozean zwischen Indien im Westen und den Philippinen im Osten, zwischen Japan im Norden und Australien im Süden. Im Jahre 2003 wurden bei einer Expedition zur Erforschung untermeerischer Canyons vor Hawaii auch Exemplare von Plesiobatis daviesi in einer Tiefe von 650 m beobachtet. Bevorzugt werden also die Meere im indo-pazifischen Raum zwischen 33° nördlicher Breite und 33° südlicher Breite.
Wegen seiner Lebensweise in tiefen und schwer zugänglichen Zonen des Kontinentalschelfs ist die Lebensweise des Tiefwasser-Stachelrochens noch wenig erforscht. Künftige Tiefwasserexpeditionen werden in diesen Lebensräumen noch viele bisher unbeschriebene Lebewesen entdecken, darunter vielleicht auch weitere Arten der Familie der Tiefwasser-Stachelrochen.
The deepwater stingray or giant stingaree (Plesiobatis daviesi) is a species of stingray and the sole member of the family Plesiobatidae. It is widely distributed in the Indo-Pacific, typically over fine sediments on the upper continental slope at depths of 275–680 m (900–2,230 ft). This species reaches 2.7 m (8.9 ft) in length and 1.5 m (4.9 ft) in width. It has an oval pectoral fin disc with a long, flexible, broad-angled snout. Most of the entire latter half of its tail supports a distinctively long, slender, leaf-shaped caudal fin. Its coloration is dark above and white below, and its skin is almost completely covered by tiny dermal denticles.
Preying on crustaceans, cephalopods, and bony fishes, the deepwater stingray may hunt both on the sea floor and well above it in open water. It is probably aplacental viviparous, with the mother supplying her gestating young with histotroph ("uterine milk"). Captured rays merit caution due to their long, venomous stingers. This species is taken by deepwater commercial fisheries, but in numbers too small to significantly threaten its population. Therefore, the International Union for Conservation of Nature has assessed it as Least Concern.
The first scientific description of the deepwater stingray was authored by John H. Wallace, as part of a 1967 Investigational Report from the Oceanographic Research Institute, Durban. He named the new species daviesi in honor of David H. Davies, the late director of the ORI, and placed it in the genus Urotrygon based on its long, low caudal fin and lack of a dorsal fin. The type specimens were collected during September 1996 near the Limpopo River mouth in Mozambique: the holotype is a mature male 92 cm (36 in) across, and the paratype is an immature male 33 cm (13 in) across.[3] Other common names for this species include Davies' stingray and giant stingray.[4]
In a 1990 morphological phylogenetic study, Kiyonori Nishida concluded that the deepwater stingray and the sixgill stingray (Hexatrygon bickelli) were the most basal stingrays (suborder Myliobatoidei). Therefore, he moved this species to its own genus, Plesiobatis, and family, Plesiobatidae; the name is derived from the Greek plesio ("primitive") and batis ("ray").[5] Subsequent morphological studies have corroborated the basal position of Plesiobatis, but disagreed on its relationships to nearby taxa. John McEachran, Katherine Dunn, and Tsutomu Miyake in 1996 could not fully resolve the position of Plesiobatis, thus they assigned it provisionally to the family Hexatrygonidae.[6] McEachran and Neil Aschliman in 2004 found Plesiobatis to be the sister taxon of Urolophus, and recommended that it be placed in the family Urolophidae.[7] Until the phylogeny is better-resolved, authors have tended to preserve the family Plesiobatidae.[2][8]
Records of the deepwater stingray come from a number of locations scattered widely in the Indo-Pacific: KwaZulu-Natal in South Africa and Mozambique, the Gulf of Mannar, the northern Andaman Islands, the South China Sea, the Ryukyu Islands and the Kyushu–Palau Ridge, along the southern coastline of Australia, northwestern Australia from the Rowley Shoals to Shark Bay, northeastern Australia from Townsville to Wooli, New Caledonia, and Hawaii.[1][9][10][11] This bottom-dwelling species generally inhabits the upper continental slope at depths of 275–680 m (900–2,230 ft), over muddy or silty substrates.[11] An anomalous record from only 44 m (144 ft) deep off Mozambique was made. It seems to be locally common in tropical Australian waters, but may be rarer elsewhere.[1]
The deepwater stingray has a flabby body,[11] with enlarged pectoral fins forming a disc usually longer than it is wide. The leading margins of the disc converge at a broad angle. The snout is thin and measures over six times as long as the diameter of the orbit; the snout tip protrudes slightly from the disc. The small eyes are positioned just ahead of the spiracles, which have angular posterior rims. The large, circular nostrils are placed close to the mouth, to which they are connected by a pair of broad grooves. Between the nostrils is a broad curtain of skin with a strongly fringed posterior margin. The wide, straight mouth contains 32–60 tooth rows in either jaw, increasing in number with age. Each tooth is small with a low, blunt cusp; in adult males the teeth at the center are sharp and backward-pointing. The five pairs of gill slits are small and placed beneath the disc.[2][10]
The pelvic fins are small and have blunt outer corners. The moderately thick tail measures 93–102% as long as the disc and lacks lateral skin folds and dorsal fins. One or two serrated stinging spines are present atop the tail, just ahead of the halfway point. The slender caudal fin originates a short distance behind the sting; it is symmetrical above and below, and terminates in a rounded leaf-like shape. The skin is densely covered by fine dermal denticles, that become sparse to absent on the pelvic fins, towards the ventral disc margin, and around the mouth. The deepwater stingray is purplish brown to blackish above; some rays also have irregular darker blotches and spots. The underside is white, with a narrow dark border along the lateral disc margins. The tail is entirely dark, and the caudal fin is black. This large species grows up to 2.7 m (8.9 ft) long, 1.5 m (4.9 ft) across, and 118 kg (260 lb) in weight off southern Africa, though it is not known to exceed 2.0 m (6.6 ft) long off Australia.[2][3][10]
The diet of the deepwater stingray consists of cephalopods, crustaceans (including penaeid prawns, crabs, and lobsters), and bony fishes (including eels).[1][4] Its long, flexible snout is well-suited for rooting through sediment, while the presence of mesopelagic species in its diet suggest that it may also hunt well above the sea floor.[11] One recorded individual was found severely gouged by kitefin sharks (Dalatias licha), which are capable of excising plugs of flesh, cookiecutter-like, from larger animals.[2] The deepwater stingray is presumed to be similar to other stingrays in being aplacental viviparous, and having the developing embryos nourished by maternally produced histotroph ("uterine milk"). Given its large size and deepwater habits, it is probably not highly prolific, with a small litter size and a long gestation period. The young are apparently born at close to 50 cm (20 in) long, as evidenced by the capture of a free-living specimen of that size that still bore a yolk sac scar. Males and females mature sexually at 1.3–1.7 m (4.3–5.6 ft) and 1.9–2.0 m (6.2–6.6 ft) long respectively. The maximum size, and likely also the maturation size, varies between geographic regions.[1][2][10]
When captured, the deepwater stingray flails its powerful tail violently, and its long, venomous sting can inflict a serious injury to a fishery worker. It is caught incidentally by deepwater bottom trawls and longlines; the meat may be sold but is poorly regarded.[10][11] None of the deepwater commercial fisheries operating within its range (including those off South Africa, Taiwan, Indonesia and Australia) are extensive, and thus only small numbers of deepwater stingrays are landed. As a result, the International Union for Conservation of Nature has determined this species to be minimally threatened by human activity, and listed it under least concern. However, should deepwater fisheries expand in the future, it may be susceptible to depletion due to its probable rarity and low reproductive rate.[1]
The deepwater stingray or giant stingaree (Plesiobatis daviesi) is a species of stingray and the sole member of the family Plesiobatidae. It is widely distributed in the Indo-Pacific, typically over fine sediments on the upper continental slope at depths of 275–680 m (900–2,230 ft). This species reaches 2.7 m (8.9 ft) in length and 1.5 m (4.9 ft) in width. It has an oval pectoral fin disc with a long, flexible, broad-angled snout. Most of the entire latter half of its tail supports a distinctively long, slender, leaf-shaped caudal fin. Its coloration is dark above and white below, and its skin is almost completely covered by tiny dermal denticles.
Preying on crustaceans, cephalopods, and bony fishes, the deepwater stingray may hunt both on the sea floor and well above it in open water. It is probably aplacental viviparous, with the mother supplying her gestating young with histotroph ("uterine milk"). Captured rays merit caution due to their long, venomous stingers. This species is taken by deepwater commercial fisheries, but in numbers too small to significantly threaten its population. Therefore, the International Union for Conservation of Nature has assessed it as Least Concern.
Plesiobatis daviesi arrain miliobatiformeen espeziea da, Indiako ozeanoan eta Ozeano Barean bizi dena. Bere genero eta familian kide bakarra da, hau da, monotipikoa. 2,7 metroko luzera eta 1,5 metroko zabalera ere izan ditzake.
Artikulu hau biologiari buruzko zirriborroa da. Wikipedia lagun dezakezu edukia osatuz. Plesiobatis daviesi arrain miliobatiformeen espeziea da, Indiako ozeanoan eta Ozeano Barean bizi dena. Bere genero eta familian kide bakarra da, hau da, monotipikoa. 2,7 metroko luzera eta 1,5 metroko zabalera ere izan ditzake.
Syvännerausku (Plesiobatis daviesi) on syvissä vesissä Intian valtameressä ja Tyynessämeressä tavattava rustokala. Se on ainoa laji syvännerauskujen heimossa (Plesiobatidae).
Aikaisemmin syvännerausku sijoitettiin sukuun Urotrygon ja kiekkorauskujen heimoon (Urolophidae). Se on kuitenkin ulkomuodoltaan erilainen ja sijoitettiin vuonna 1990 omaan heimoonsa.[1][3][4][5][6]
Syvännerausku on kookas kala ja voi kasvaa jopa 2,7 metriä pitkäksi. Koiraat tulevat sukukypsiksi noin 130 cm pituisina ja naaraat kookkaampina noin 189–200 cm mittaisina. Ruumis on litteä ja suuret rintaevät antavat kalalle pyöreän muodon. Evissä on pieniä piikkejä. Pyrstö on lähes yhtä pitkä kuin muu ruumis ja melko ohut. Pyrstössä on pitkä myrkyllinen piikki, joka voi aiheuttaa ihmisellekin tuskallisen haavan. Lajin lisääntymisestä ei ole tietoa, mutta se on todennäköisesti vivipaarinen eli synnyttää eläviä poikasia. Lajin hampaat ovat melko pienet ja teräväkärkiset[1][4][6][5][7]
Syvännerauskuja tavataan Etelä-Afrikan ja Mosambikin rannikoilta, Australian ja Kaakkois-Aasian rannikkoseuduilta ja Havaijilta. Laji elää pehmeällä merenpohjalla 44–780 metrin syvyydestä merenpinnasta. Syvännerauskujen ravintoa ovat muut kalat, erityisesti ankeriaat, äyriäiset ja nilviäiset. Sitä saadaan joskus sivusaaliina trooleilla ja sen liha on syötävää muttei erityisen arvostettua.[1][4][5][6][7]
Syvännerausku (Plesiobatis daviesi) on syvissä vesissä Intian valtameressä ja Tyynessämeressä tavattava rustokala. Se on ainoa laji syvännerauskujen heimossa (Plesiobatidae).
La pastinaca abissale (Plesiobatis daviesi), o pastinaca gigante, è l'unica specie di razza della famiglia dei Plesiobatidi. È la più grande e la maggiormente diffusa tra tutte le pastinache e vive sulle scarpate continentali dal Sudafrica fino al Giappone e all'Australia[2]. È strettamente imparentata con le specie del genere Urolophus (famiglia Urolofidi), con le quali forma un gruppo monofiletico[3].
La pastinaca abissale ha una distribuzione sporadica che ricopre l'Oceano Indiano e il Pacifico occidentale e centrale. È stata avvistata al largo delle coste del Natal, sulla costa orientale del Sudafrica, del Mozambico, dell'India meridionale, nel Mar Cinese meridionale al largo della Cina, lungo la dorsale Kyushu-Palau, nelle Isole Ryukyu, nella Shark Bay e nelle Rowley Shoals al largo dell'Australia Occidentale, a Townsville (Queensland), a Wooli (Nuovo Galles del Sud) e alle Hawaii[4]. Questa specie vive in acque più profonde di quelle abitate dalle altre pastinache della famiglia degli Urolofidi ad essa imparentate e generalmente si incontra sul soffice substrato della parte superiore delle scarpate continentali a profondità di 275-680 metri (350-680 metri in Australia). Solo una volta è stata avvistata a 44 metri di profondità sulla piattaforma continentale al largo del Mozambico[1].
La pastinaca abissale, la più grande tra tutte le pastinache, raggiunge i 270 centimetri di lunghezza (200 centimetri in Australia)[1]. Di costituzione robusta, ha una coda piuttosto corta e tronca, sulla quale, dietro le pinne pelviche, è situata una spina dentellata molto appuntita. Il muso è piuttosto allungato e appuntito; gli occhi sono piccoli e posti proprio davanti agli spiracoli. Le alette nasali anteriori sono fuse in una cortina nasale che non raggiunge la bocca. La bocca è diritta e larga, con piccoli denti dalla punta ovale muniti di corte cuspidi sulla corona. Su ogni mascella vi sono 32-60 denti, più numerosi negli adulti che nei giovani. Le pinne dorsali sono assenti e la pinna caudale, a forma di foglia, è lunga, piuttosto grande e simmetrica sopra e sotto la coda. Molto simile alle razze rotonde, si distingue da esse per avere la superficie superiore ricoperta da piccoli e sottili denticoli dermici. La colorazione è marrone violacea o grigio violacea sul dorso, talvolta ricoperto da chiazze o macchie irregolari scure, e bianca sul ventre con i margini del disco più scuri. La coda è completamente scura[4].
La pastinaca abissale si nutre di pesci, gamberi peneidi, granchi, aragoste e cefalopodi. La sua dieta comprende specie mesopelagiche, il che suggerisce che migri nella colonna d'acqua. La riproduzione è probabilmente vivipara, ma ulteriori dettagli sono sconosciuti; a causa delle grandi dimensioni e dell'habitat abissale in cui vive, è probabile che partorisca nidiate poco numerose dopo un lungo periodo di gestazione. Un esemplare di 50 centimetri catturato vivo presentava una cicatrice ombelicale. Il più piccolo maschio adulto conosciuto era lungo 130 centimetri; le dimensioni alla maturità variano probabilmente a seconda delle località[1].
Questa specie viene catturata con reti a strascico e palamiti di profondità, ma non in gran numero in ogni parte del suo areale. Nelle aree in cui vive è molto comune e la Lista rossa IUCN la classifica tra le specie non in pericolo[1]. La carne viene utilizzata, ma non è di gran valore[2]. Quando viene trascinata a terra, questa razza agita con vigore la potente coda e, a causa della sua lunga spina, deve essere maneggiata con cura[4].
La pastinaca abissale (Plesiobatis daviesi), o pastinaca gigante, è l'unica specie di razza della famiglia dei Plesiobatidi. È la più grande e la maggiormente diffusa tra tutte le pastinache e vive sulle scarpate continentali dal Sudafrica fino al Giappone e all'Australia. È strettamente imparentata con le specie del genere Urolophus (famiglia Urolofidi), con le quali forma un gruppo monofiletico.
De reuzendoornrog (Plesiobatis daviesi) is een rog uit een monotypisch geslacht en een monotypische familie. Zoals de naam al aangeeft is dit de grootste doornrog. De gemiddelde lengte van een volwassen reuzendoornrog ligt tussen de 1,9 en 2,0 meter, ze kunnen maximaal 2,7 m lang worden.
Het verspreidingsgebied van de reuzendoornrog reikt in de Indische Oceaan van de zuidoostkust van Afrika (Zuid-Afrika en Mozambique) tot het zuiden van India in de Grote Oceaan van Japan via de Filipijnen tot Australië en verder tot aan Hawaï. Deze doornrog leeft op een diepte tussen de 50-800 m onder het wateroppervlak op zeebodems met een zachte ondergrond. Ze foerageren op kleine vissen, krabben, garnalen, kreeften, inktvissen en borstelwormen.
In 2003, tijdens een onderzoekexpeditie in een onderzeese kloof bij Hawaï werden reuzendoornroggen waargenomen op een diepte van 650 m.[2]
Omdat de reuzendoornrog leeft in diepe en moeilijke toegankelijke zeegebieden van het continentaal plat, is er relatief weinig over hem bekend. De vis wordt als bijvangst door de beroepsvisserij met lange lijnen en sleepnetten op grote diepte gevangen. Het visvlees wordt wel gebruikt, maar wordt niet hoog gewaardeerd. Bij het aan boord brengen van de reuzendoornrog bestaat het risico op verwondingen door de lange giftige stekel in de staart. De visserij vormt geen bedreiging voor de populatiegrootte en daarom staat hij als niet bedreigd op de internationale rode lijst.[1]
Bronnen, noten en/of referentiesDe reuzendoornrog (Plesiobatis daviesi) is een rog uit een monotypisch geslacht en een monotypische familie. Zoals de naam al aangeeft is dit de grootste doornrog. De gemiddelde lengte van een volwassen reuzendoornrog ligt tussen de 1,9 en 2,0 meter, ze kunnen maximaal 2,7 m lang worden.
Рацион Plesiobatis daviesi состоит из головоногих, ракообразных (креветок, крабов и омаров) и костистых рыб. Длинное и гибкое рыло хорошо приспособлено, чтобы копаться в осадках, тогда как присутствие в рационе мезопелагических животных говорит о том, что эти скаты могут охотиться не только у дна[13]. На одной особи обнаружили многочисленные следы от укусов чёрных акул, которые способны выкусывать у своих жертв, превышающих их размерами, куски мяса из тела[10].
Plesiobatis daviesi размножаются живорождением, эмбрионы питаются желтком и гистотрофом. Учитывая крупный размер и глубоководную среду обитания, можно сделать вывод о том, что это медленно размножающийся вид скатов с немногочисленным помётом и длительным сроком вынашивания. Длина новорожденных около 50 см. Попадались молодые скаты примерно такой длины с остатками шрама от желточного мешка. Самцы и самки достигают половой зрелости при длине 1,3—1,7 м и 1,9—2 м соответственно[2][2][10][12].
Plesiobatis daviesi не представляют интереса для коммерческого промысла. Будучи пойманными они яростно молотят хвостом и способны нанести рыбаку серьёзные раны. Их мясо съедобно, но ценится невысоко[12][13]. В их ареале подводный лов не ведётся интенсивно, так что они лишь в небольшом количестве попадаются в качестве прилова. Международный союз охраны природы присвоил этому виду статус сохранности «Вызывающий наименьшие опасения»[2].
深水尾魟屬是板鰓亞綱燕魟目的其中一科。僅有一屬一種，即達氏近魟又稱達氏深水尾魟(Plesiobatis daviesi)。
保全状況評価[1] LEAST CONCERN
分類 界 : 動物界 Animalia 門 : 脊索動物門 Chordata 綱 : 軟骨魚綱 Chondrichthyes 亜綱 : 板鰓亜綱 Elasmobranchii 目 : トビエイ目 Myliobatiformes 科 : ウスエイ科 PlesiobatidaeUrolophus marmoratus Chu, Hu & Li, 1981
Urotrygon daviesi J. H. Wallace, 1967
ウスエイ(薄鱏、Plesiobatis daviesi)はトビエイ目に属するエイの一種。ウスエイ科、ウスエイ属は単型。インド太平洋に広く分布し、細かい堆積物に覆われた深度275-680mの上部大陸斜面に生息する。体長2.7m・体幅1.5mになる。丸い体盤、柔らかく長い吻を持つ。尾の後半は細長い葉状の尾鰭となる。体の上面は暗色で下面は白、皮膚は小さな皮歯に覆われる。
甲殻類・頭足類・魚類を食べる。おそらく無胎盤性胎生。捕獲した場合には尾の毒棘に注意する必要がある。底引き網などで漁獲されるがその量は少ないため、IUCNは軽度懸念としている。
最初の記載は1967年、John H. Wallaceが、ダーバンのOceanographic Research Institute(ORI)による調査の一環として行った。この時点では長く低い尾鰭、背鰭の欠如などの特徴に基づいてUrotrygon属とされた。種小名はその後ORIの所長となったDavid H. Daviesへの献名としてdaviesiとされた。タイプ標本は1996年9月、モザンビークのリンポポ川河口近くで採集され、ホロタイプは体幅92cmの成熟雄、パラタイプは体幅33cmの未成熟雄[3]。
西田清徳は1990年の形態系統解析により、ウスエイはムツエラエイ(Hexatrygon bickelli)とともに、トビエイ亜目の基底クレードを構成すると結論した。その結果ウスエイは古代ギリシア語のplesio(原始的な)、batis(エイ)に由来するPlesiobatis属に移された[4]。その後の研究でもこれは支持されたが、他のタクソンとの関係は否定された。1996年のJohn McEachran・Katherine Dunn・三宅 力による研究では、ウスエイの系統的位置は十分に明らかにならず、暫定的にムツエラエイ科とされた[5]。2004年のMcEachranとNeil Aschlimanによる研究では、ウスエイはヒラタエイ属(Urolophus)の姉妹群となり、ヒラタエイ科に含めることが推奨された[6]が、さらなる検証が行われるまではウスエイ科を残すべきだとしている[2][7]。
インド太平洋に広く分布し、南アフリカのクワズール・ナタール州・モザンビーク・マンナール湾・北部アンダマン諸島・南シナ海・南西諸島・九州パラオ海嶺・オーストラリア北西部のローリー・ショールズからシャーク湾・オーストラリア北東部のタウンズビルからWooli・ニューカレドニア・ハワイで記録されている[1][8][9][10]。底生魚で深度275-680m、泥やシルトに覆われた上部大陸斜面に生息する[10]。モザンビーク沖の深度44mから得られたこともある。オーストラリア熱帯域では一般的であるようだが、他の場所では稀種[1]。
体は柔らかく[10]、体盤は幅より長さのほうが長い。前縁は吻に向けて尖る。吻は薄く、長さは眼窩径の6倍以上。眼は小さく、後縁が角張った噴水孔のすぐ前にある。鼻孔は大きくて丸く、広い溝で口とつながる。鼻孔間には皮膚の弛みがあり、その後縁は強く縁取られる。広く真っ直ぐな口には32–60の歯列が並び、年齢と共に増える。歯は小さく鈍いが、成体雄の中央の歯は鋭く後ろを向く。5対の小さい鰓裂が体盤下面に並ぶ[2][9]。
腹鰭は小さく、外側の角は丸い。少し太い尾は体盤長の93–102%になり、背鰭を欠く。1-2本の鋸歯状の棘が、尾のやや基部寄り上部から生える。細く上下対称な尾鰭は棘のすぐ後方から始まり、後縁は丸い葉状。皮膚は細かく密な皮歯に覆われるが、腹鰭・体盤腹側縁・口周辺は覆わない。体色は紫がかった茶から黒。暗い斑点を持つ個体もいる。下面は白だが体盤後縁は暗色。尾は全体的に暗色で、尾鰭は黒。南アフリカ沖で獲れた大型個体は体長2.7m・体幅1.5m・重量118kgだったが、オーストラリア沖では体長2mを超える固体は知られていない[2][3][9]。
餌は頭足類・甲殻類(クルマエビ類・カニ・ロブスターなど)・硬骨魚(ウナギなど)[1][11]。長く柔軟な吻は 堆積物中の餌を探すのに適するが、中深層種も捕食しているため、海底から離れて餌を探すこともあると考えられる[10]。ヨロイザメ(Dalatias licha)に肉を抉られた個体が発見されている[2]。他のアカエイ類と同様に胚を組織栄養(子宮乳)で育てる無胎盤性胎生と予想されている。深海性でサイズが大きいため、産仔数は少なく、妊娠期間は長いと考えられている。卵黄嚢の跡が残る捕獲個体によると、稚魚は体長50cm。雄は体長1.30-1.72m、雌は1.89-2.00mで性成熟する。最大サイズや成熟サイズは生息地によって変化する[1][2][9]。
捕獲時には尾の毒棘を振り回すため、漁業者が被害にあうことがある。深海底引き網や延縄で混獲されるが、肉質は悪い[9][10]。生息域(南アフリカ・台湾・インドネシア・オーストラリア)で大規模な深海商業漁業が行われておらず、水揚げ量も極僅かであるため、IUCNは軽度懸念としている。だが将来的に深海漁業が活発になると、繁殖力が低いために減少することが予想される[1]。
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ウスエイ(薄鱏、Plesiobatis daviesi)はトビエイ目に属するエイの一種。ウスエイ科、ウスエイ属は単型。インド太平洋に広く分布し、細かい堆積物に覆われた深度275-680mの上部大陸斜面に生息する。体長2.7m・体幅1.5mになる。丸い体盤、柔らかく長い吻を持つ。尾の後半は細長い葉状の尾鰭となる。体の上面は暗色で下面は白、皮膚は小さな皮歯に覆われる。
甲殻類・頭足類・魚類を食べる。おそらく無胎盤性胎生。捕獲した場合には尾の毒棘に注意する必要がある。底引き網などで漁獲されるがその量は少ないため、IUCNは軽度懸念としている。
긴꼬리흰가오리[3], 또는 심해가오리(Plesiobatis daviesi)는 매가오리목에 속하는 연골어류의 일종이다.[4] 긴꼬리흰가오리과(Plesiobatisidae)와 긴꼬리흰가오리속(Plesiobatis)의 유일종이다. 인도-태평양에 널리 분포하며, 수심 275-1680m 깊이의 대륙사면 상단의 입자가 고운 퇴적물 위에서 주로 발견된다. 몸길이는 최대 2.8m, 너비는 1.5m 정도이다.
긴꼬리흰가오리, 또는 심해가오리(Plesiobatis daviesi)는 매가오리목에 속하는 연골어류의 일종이다. 긴꼬리흰가오리과(Plesiobatisidae)와 긴꼬리흰가오리속(Plesiobatis)의 유일종이다. 인도-태평양에 널리 분포하며, 수심 275-1680m 깊이의 대륙사면 상단의 입자가 고운 퇴적물 위에서 주로 발견된다. 몸길이는 최대 2.8m, 너비는 1.5m 정도이다.
