Malta country information

Common names: Raja petruza, Raja tal-fosos, Razza chiodata
Occurrence: native
Salinity: marine
Abundance: | Ref:
Importance: | Ref:
Aquaculture: | Ref:
Regulations: | Ref:
Uses: no uses
Comments: Also Ref. 3167.
National Checklist:
Country Information: httpss://www.cia.gov/library/publications/resources/the-world-factbook/geos/mt.html
National Fisheries Authority:
Occurrences: Occurrences Point map
Main Ref: Lanfranco, G.G., 1996
National Database:

Classification / Names

Elasmobranchii (sharks and rays) > Rajiformes (Skates and rays) > Rajidae (Skates)
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL

Common names from other countries

Лисица морская (=скат колючий), Raie bouclée, Raya de clavos, ... more

Main reference

McEachran, J.D. and K.A. Dunn. 1998. (Ref. 27314)
References | Biblio | Coordinator : McEachran, John | Collaborators

Size / Weight / Age

Max length : 105 cm TL male/unsexed; (Ref. 53748); 139.0 cm TL (female); common length : 85.0 cm TL male/unsexed; (Ref. 9987); max. published weight: 18.0 kg (Ref. 35388); max. reported age: 15 years (Ref. 41305)

Length at first maturity
L_m 76.6, range 47 - 87.5 cm

Environment

Marine; demersal; depth range 10 - 577 m (Ref. 56504)

Climate / Range

Subtropical, preferred 17°C (Ref. 107945); 70°N - 29°S, 25°W - 42°E

Distribution

Eastern Atlantic: Iceland, Norway, North Sea and the western Baltic southward to Morocco and Namibia, including the Mediterranean and the Black Sea. Although reported from southern Africa, its status in the area is uncertain (Ref. 5578).
Countries | FAO areas | Ecosystems | Occurrences | Introductions

Short description

Dorsal spines (total): 0; Anal spines: 0; Anal soft rays: 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).

Inhabits shelf and upper slope waters. Depth range 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). 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). 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).

IUCN Red List Status (Ref. 115185)

Near Threatened (NT)

Threat to humans

Harmless

Human uses

Fisheries: commercial; gamefish: yes

More information

Countries
FAO areas
Ecosystems
Occurrences
Introductions
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Ecology
Diet
Food items
Food consumption
Ration

Common names
Synonyms
Metabolism
Predators
Ecotoxicology
Reproduction
Maturity
Spawning
Fecundity
Eggs
Egg development

Age/Size
Growth
Length-weight
Length-length
Length-frequencies
Morphometrics
Morphology
Larvae
Larval dynamics
Recruitment
Abundance

References
Aquaculture
Aquaculture profile
Strains
Genetics
Allele frequencies
Heritability
Diseases
Processing
Mass conversion

Collaborators
Pictures
Stamps, Coins
Sounds
Ciguatera
Speed
Swim. type
Gill area
Otoliths
Brains
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Tools

Special reports

Check for Aquarium maintenance | Check for Species Fact Sheets | Check for Aquaculture Fact Sheets

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Summary page | Point data | Common names | Photos

Internet sources

Estimates of some properties based on models

Phylogenetic diversity index (Ref. 82805)
PD₅₀ = 0.5000 many relatives (e.g. carps) 0.5 - 2.0 few relatives (e.g. lungfishes)

Trophic Level (Ref. 69278)
3.8 ±0.2 se; Based on diet studies.

Resilience (Ref. 69278)
Low, minimum population doubling time 4.5 - 14 years (K=0.09-0.14; tm=10; tmax=23; Fec=150)

Vulnerability (Ref. 59153)
High to very high vulnerability (72 of 100)

Price category (Ref. 80766)
Medium

Raja clavata Linnaeus, 1758