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Rhizoprionodon acutus (Rüppell, 1837)

Milk shark
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Native range | All suitable habitat | Point map | Year 2050
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Rhizoprionodon acutus   AquaMaps   Data sources: GBIF OBIS
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Australia country information

Common names: Blacktip shark, Fish shark, Little blue shark
Occurrence: native
Salinity: brackish
Abundance: | Ref:
Importance: | Ref:
Aquaculture: | Ref:
Regulations: | Ref:
Uses: no uses
Comments: Occurs in northern Australia, from Shark Bay in Western Australia to Fraser Island in Queensland (Ref. 6871). Recorded from Shark Bay (Ref. 115274). Bycatch of Taiwanese and Thai demersal trawlers fishing in northern Australia (Ref. 6871). Also Ref. 7300, 33390.
National Checklist:
Country Information: https://www.cia.gov/library/publications/resources/the-world-factbook/geos/as.html
National Fisheries Authority: http://www.csiro.au/
Occurrences: Occurrences Point map
Main Ref: Last, P.R. and J.D. Stevens, 1994
National Database:

Common names from other countries

Classification / Names Κοινά ονόματα | Συνώνυμα | Catalog of Fishes(Γένος, Είδη) | ITIS | CoL | WoRMS | Cloffa

Ελασμοβράγχιοι (καρχαρίες και σαλάχια) (sharks and rays) > Carcharhiniformes (Ground sharks) > Carcharhinidae (Requiem sharks)
Etymology: Rhizoprionodon: rhiza (Gr.), root; prion (Gr.) saw; odon (Gr.), tooth, referring to teeth with serrated (saw-like) bases, or roots [replacement name for Rhizoprion Ogilby 1915, preoccupied by Rhizoprion Jourdan 1861 in mammals]. (See ETYFish);  acutus: Latin for sharp or pointed, probably referring to narrow, pointed snout. (See ETYFish).
  More on author: Rüppell.

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

Θαλασσινό(ά); Γλυκού νερού; Υφάλμυρο βενθοπελαγικό; αμφίδρομο (Ref. 51243); εύρος βάθους 1 - 200 m (Ref. 244).   Tropical; 41°N - 30°S, 27°W - 156°E

Κατανομή Χώρες | Περιοχές FAO | Οικοσυστήματα | Παρουσίες | Point map | Εισαγωγές | Faunafri

Eastern Atlantic: Madeira and Mauritania to Angola (Ref. 244). Indo-West Pacific: Persian Gulf (Ref. 68964), Red Sea and East Africa to Indonesia, north to Japan, south to Australia. Also reported from Gulf of Taranto in Mediterranean Sea (Ref. 231).

Length at first maturity / Μέγεθος / Βάρος / Age

Maturity: Lm 75.0, range 70 - 80 cm
Max length : 175 cm TL αρσενικό/απροσδιόριστο; (Ref. 12693); 80.8 cm TL (female); common length : 110 cm TL αρσενικό/απροσδιόριστο; (Ref. 47737); μεγ. δημοσιευμένο βάρος: 5.0 kg (Ref. 40637); μεγ. αναφερόμενη ηλικία: 8 έτη (Ref. 244)

Short description Κλείδες προσδιορισμού | Μορφολογία | Μορφομετρία

Ραχιαίες άκανθες (συνολικά) : 0; Εδρικές άκανθες: 0. A small shark with a long, narrow, snout, big eyes without notches, long labial furrows, and oblique-cusped teeth which may be smooth-edged or weakly serrated; 2nd dorsal fin small, low and behind larger anal fin; no interdorsal ridge (Ref. 5578). Grey or grey-brown above, white below (Ref. 5578). Dorsal and anal fins with dusky or blackish edges, fins slightly darker than back (Ref. 9997).

Βιολογία     Γλωσσάρι (π.χ. epibenthic)

Found on continental shelves, often on sandy beaches and rarely in estuaries (Ref. 244). Reported to enter freshwater and recorded several times from Cambodia as far upstream as the Great Lake (Ref. 12693). Occurs near the surface in shallow waters (Ref. 12693). Feeds mainly on small pelagic and benthic bony fishes, also cephalopods and other invertebrates (Ref. 244). Viviparous (Ref. 50449). Utilized fresh and possibly dried salted for human consumption and for fishmeal (Ref. 9997). The 178 cm specimen recorded off Africa is possibly based on some other species (Ref. 9997).

Life cycle and mating behavior Maturities | Αναπαραγωγή | Spawnings | Egg(s) | Fecundities | Προνύμφες

Distinct pairing with embrace (Ref. 205). Viviparous, with a yolk-sac placenta; 2 to 8 in a litter (Ref. 9997), usually 2 to 5 after a gestation period of ~ 12 months; no seasonality in the reproductive cycle (Ref.58048). Size at birth between 25 and 39 cm.

Main reference Upload your references | Αναφορές | Συντονιστής : Compagno, Leonard J.V. | Συνεργάτες

Compagno, L.J.V., 1984. FAO Species Catalogue. Vol. 4. Sharks of the world. An annotated and illustrated catalogue of shark species known to date. Part 2 - Carcharhiniformes. FAO Fish. Synop. 125(4/2):251-655. Rome: FAO. (Ref. 244)

IUCN Red List Status (Ref. 130435)

  Ευάλωτο, βλέπε Κόκκινη Λίστα (VU) (A2bd); Date assessed: 04 February 2020

CITES (Ref. 128078)


CMS (Ref. 116361)

Not Evaluated

Threat to humans

  Harmless (Ref. 244)




Human uses

αλιεία: Εμπορικό(ά); αλιεία αναψυχής: ναί

Περισσότερες πληροφορίες

Trophic ecology
Τροφικά αντικείμενα
Diet compositions
Food consumptions
Food rations
Θηρευτές
Ecology
Οικολογία
Home ranges
Population dynamics
Growths
Max. ages / sizes
Length-weight rel.
Length-length rel.
Length-frequencies
Mass conversions
Recruitments
Abundances
Life cycle
Αναπαραγωγή
Maturities
Fecundities
Spawnings
Spawning aggregations
Egg(s)
Egg developments
Προνύμφες
Δυναμική προνυμφών
Anatomy
Gill areas
Εγκέφαλοι
Otoliths
Physiology
Body compositions
Nutrients
Oxygen consumptions
Κολυμβητικός τύπος
Swimming speeds
Visual pigment(s)
Ήχοι ψαριών
Diseases / Parasites
Toxicities (LC50s)
Genetics
Γενετική
Electrophoreses
Heritabilities
Human related
Aquaculture systems
Προφίλ υδατοκαλλιεργειών
Στελέχοι
Ciguatera cases
Stamps, coins, misc.
References
Αναφορές

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Διαδικτυακές πηγές

Estimates based on models

Preferred temperature (Ref. 115969): 19.6 - 28.5, mean 26.9 (based on 1463 cells).
Phylogenetic diversity index (Ref. 82804):  PD50 = 0.5078   [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00339 (0.00273 - 0.00421), b=3.08 (3.04 - 3.12), in cm Total Length, based on LWR estimates for this species (Ref. 93245).
Τροφικό Επίπεδο (Ref. 69278):  4.3   ±0.4 se; based on diet studies.
Ελαστικότητα (Ref. 120179):  Πολύ χαμηλό, ελάχιστος χρόνος για διπλασιασμό πληθυσμού > 14 έτη (K=0.2-0.6; Fec=1).
Fishing Vulnerability (Ref. 59153):  High vulnerability (61 of 100).
Price category (Ref. 80766):   Medium.