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Raja clavata Linnaeus, 1758

Thornback ray
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Raja clavata   AquaMaps   Data sources: GBIF OBIS
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Image of Raja clavata (Thornback ray)
Raja clavata
Picture by Stergiou, K.I.


United Kingdom country information

Common names: Dinnan, Doctot, Flair
Occurrence: native
Salinity: marine
Abundance: abundant (always seen in some numbers) | Ref: Ellis, J.R., A. Cruz-Martinez, B.D. Rackham and S.I. Rodgers, 2005
Importance: | Ref:
Aquaculture: | Ref:
Regulations: | Ref:
Uses: no uses
Comments: Widespread around the British Isles (7-192 m), although more abundant along the southern and western coasts, where maximum catch rates were ca. 200 ind/hr. Most abundant rajid in the surveys. Catches in the central and northern North Sea were patchy. A high relative abundance of juveniles were recorded in the Thames Estuary, northeastern English Channel, northern Bristol Channel, Cardigan Bay, Luce Bay and Solway Firth (Ref. 82399).
National Checklist:
Country Information: https://www.cia.gov/library/publications/resources/the-world-factbook/geos/uk.html
National Fisheries Authority:
Occurrences: Occurrences Point map
Main Ref: Muus, B. and P. Dahlström, 1978
National Database:

Common names from other countries

Classification / Names প্রচলিত নাম সমূহ | প্রতিনাম সমূহ | Catalog of Fishes(গণ , প্রজাতি ) | ITIS | CoL | WoRMS | Cloffa

ইলাসমোব্রাঙ্কি (হাঙ্গর এবং রে) (sharks and rays) > Rajiformes (Skates and rays) > Rajidae (Skates)
Etymology: Raja: Latin, raja, -ae = a sting ray (Raja sp.) (Ref. 45335).
  More on author: Linnaeus.

Environment: milieu / climate zone / depth range / distribution range বাস্তুসংস্থান

সামুদ্রিক তলদেশ বিহারী; গভীরতার পরিসীমা 5 - 1020 m (Ref. 114953).   Subtropical; 70°N - 38°S, 25°W - 50°E

বিতরণ দেশ সমূহ | এফ এ ও এলাকাসমূহ | বাস্তুতন্ত্র | দৃষ্টিগোচর | Point map | প্রচলন | Faunafri

Eastern Atlantic and Southwest Indian Ocean: Iceland to Madagascar, including the Mediterranean Sea.

Length at first maturity / আকৃতি / ওজন / Age

Maturity: Lm 76.6, range 47 - 87.5 cm
Max length : 105 cm TL পুরুষ/ লিঙ্গ অনিধর্ারিত ; (Ref. 53748); 139.0 cm TL (female); common length : 85.0 cm TL পুরুষ/ লিঙ্গ অনিধর্ারিত ; (Ref. 9987); সবের্াচ্চ প্রকাশিত ওজন : 18.0 kg (Ref. 35388); সর্বোচ্চ উলি্ল্লখিত বয়স : 15 বৎসর (Ref. 41305)

Short description সনাক্তকারী নির্দেশক | বহিঃ অঙ্গ সংস্থান | মরফোমেট্রিক্স

পৃষ্ঠীয় কাঁটা (মোট ) : 0; পায়ূ কাঁটা : 0. Sub-rhomboid in shape with pointed wing-tips; disc-width 1,25 to 1,36 times in its length, its length 1,70 to 1,83 times in total length. Short rostrum, rounded at his extremity; pectoral fins with clear angles on lateral side; triangular pelvic fins (Ref. 39246). Dorsally prickly; large females also prickly throughout their ventral surface; juveniles and large males prickly along the margins of their discs and the underside of their snout. 30-50 thorns form a median row from the nape to the first dorsal fin; additional large 'buckler' thorns with swollen bases scattered on upper surface of disc in adults (Ref. 3167). Coloration is highly variable, with the dorsal surface having all shades of brown with dark and light spots and blotches; ventral surface white (Ref. 3167, 58137).

জীববিজ্ঞান     শব্দকোষ (উদাহরণ স্বরূপ epibenthic)

Inhabits shelf and upper slope waters. Reported depth ranges varies, from 10-300 m (Ref. 4426, 82319, 88187), and from 300-577 m in the eastern Ionian Sea (Ref. 56504); most common in coastal waters between 10-60 m depth (Ref. 58137). Tolerates low salinities (Ref. 88171). Found on mud, sand and gravel bottoms, rarely on rougher bottoms (Ref. 6808, 58137). Nocturnal species. Feeds on all kinds of bottom animals, preferably crustaceans (Ref. 3167) and fishes (Ref. 114953). Undertakes migrations with mean distances of 54-117 km per month; shows a clear annual migration cycle (Ref. 89017, 89018), moves from deeper offshore waters (10-30 m) in autumn and winter to shallower areas (<10 m) in spring (Ref. 82319). Young are non-migratory, inhabiting inshore nursery grounds (Ref. 89019, 89020, 89022); in the Bay of Douarnenez (France) they are found to remain in shallow waters for at least 2 years (Ref. 89023). Maturity age 7-8 years (Ref. 114953). Oviparous. Young may tend to follow large objects, such as their mother (Ref. 205). Detects weak electric fields generated by other organisms (prey detection and predator avoidance) but may also generate its own weak electric fields (Ref. 10311, 88171). Utilized fresh and frozen (Ref. 9987).

Life cycle and mating behavior Maturities | প্রজনন | Spawnings | Egg(s) | Fecundities | শুককীট

Oviparous. Distinct pairing with embrace. Polyandrous species (Ref. 89024). Paired eggs are laid and deposited on shallow sand, mud, pebble or gravel bottoms (Ref. 205, 89025). Up to 170 egg cases can be laid by a single female in a year (Ref. 3167), but average fecundity is much lower (around 48-74 eggs) (Ref. 3603, 31302). In northwestern Europe, egg cases are laid during spring (Ref. 3167) and in the Mediterranean during winter and spring (Ref. 3167). Egg cases are oblong capsules with stiff pointed horns at the corners, each containing one embryo (Ref. 205). Capsules are 5.0-9.0 cm long without the horns (Ref. 41250, 88187) and 3.4-6.8 cm wide (Ref. 41250). Egg cases are anchored with an adhesive film (Ref. 82399). Embryos feed solely on yolk (Ref. 50449). Egg cases hatch after about 4-5 months and pups are about 11-13 cm TL (Ref. 88864). Mating season from February to September, peaking in June (Ref. 74501). Adults observed to form same-sex aggregations during the mating season with females moving to shallower inshore waters approximately a month before the males (Ref 3603, 58137, 74501). Mating does not occur in the Baltic Sea (Ref. 82311).

Main reference Upload your references | সূত্র সংখ্যা | সমম্বয়কারী : McEachran, John | সহযোগী

McEachran, J.D. and K.A. Dunn, 1998. Phylogenetic analysis of skates, a morphologically conservative clade of elasmobranchs (Chondrichthyes: Rajidae). Copeia 1998(2):271-290. (Ref. 27314)

IUCN Red List Status (Ref. 130435)

  Near Threatened (NT) ; Date assessed: 03 October 2005

CITES (Ref. 128078)

Not Evaluated

CMS (Ref. 116361)

Not Evaluated

Threat to humans

  Harmless




Human uses

মৎস্য: বাণিজ্যিক; শিকারযোগ্য মাছ: হঁ্যা

আরো তথ্য

Life cycle
প্রজনন
Maturities
Fecundities
Spawnings
Spawning aggregations
Egg(s)
Egg developments
শুককীট
শুককীটের সত্রিুয়তা
Physiology
Body compositions
Nutrients
Oxygen consumptions
-এর সাতাঁরের ধরণ
Swimming speeds
Visual pigment(s)
মৎস্য শব্দ
Diseases / Parasites
Toxicities (LC50s)
Genetics
বংশানুগতিবিদ্যা
Electrophoreses
Heritabilities
Human related
Aquaculture systems
একুয়াকালচার নকশাসমূহ
বংশ
Ciguatera cases
Stamps, coins, misc.

হাতিয়ার

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ইন্টারনেট সুত্র

Estimates based on models

Preferred temperature (Ref. 115969): 7.1 - 15.8, mean 10.7 (based on 474 cells).
Phylogenetic diversity index (Ref. 82804):  PD50 = 0.5000   [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00200 (0.00175 - 0.00228), b=3.26 (3.23 - 3.29), in cm Total Length, based on LWR estimates for this species (Ref. 93245).
ট্রফিক পর্যায়ে (Ref. 69278):  3.8   ±0.2 se; based on diet studies.
স্থিতিস্থাপক (Ref. 120179):  নিম্ন/ , সর্বনিম্ন প্রজন দ্বিগুনের সময় ৪.৪-১৪ বৎসর (K=0.09-0.14; tm=10; tmax=23; Fec=150).
Prior r = 0.18, 95% CL = 0.12 - 0.26, Based on 4 full stock assessments.
Fishing Vulnerability (Ref. 59153):  High vulnerability (60 of 100).
Climate Vulnerability (Ref. 125649):  High vulnerability (60 of 100).
Price category (Ref. 80766):   Medium.