Rhizoprionodon acutus

(RÜPPELL, 1837)


Milk shark
Classification: Elasmobranchii Carcharhiniformes Carcharhinidae

Reference of the original description
RÜPPELL, W.P.E.S.E. (1837)
Neue Wirbelthiere zu der Fauna von Abyssinien gehörig: Fische des rothen Meeres. Frankfurt am Main, 1837: pp. 53–80, pls. 15–21

Image of the original description

<i>Rhizoprionodon acutus</i> (RÜPPELL, 1837), image of the first description in Rüppell, plate 18, fig. 4

Images of the original description (synonym)
Synonyms / new combinations and misspellings
Carcharias aaronis, Carcharias acutus, Carcharias crenidens, Carcharias eumeces, Carcharias walbeehmi, Carcharias walbeehmii, Carcharias walbenii, Carcharias (Scoliodon) acutus, Carcharias (Scoliodon) crenidens, Carcharias (Scoliodon) walbeehmi, Carcharinus acutus, Carcharinus walbeehmi, Hypoprion acutus, Protozygaena longmani, Rhizoprion crenidens, Rhizoprionodon aff. acutus, Rhizoprionodon cf. acutus, Rhizoprionodon (Rhizoprionodon) acutus, Scoliodon acutus, Scoliodon longmani, Scoliodon vagatus, Scoliodon wahlbeehmi, Scoliodon walbeehmi, Scoliodon walbeehmii, Scoliodon walbeemii, Squalus (Scoliodon) acutus

Types
Rhizoprionodon acutus
Lectotype: SMF: 2783; Paralectotype: SMF: 761;
Carcharias aaronis
Syntype: ZMB: 4453 ZMB: 2261 ZMB: 4456
Carcharias eumeces
Holotype: MW: PI 2; Paratype: NMW: 61212;
Carcharias (Scoliodon) crenidens
Holotype: SMNS: 2449;
Scoliodon longmani
Holotype: QM: I.292;
Scoliodon vagatus
Holotype: MCZ: 401-S

Images of types

Description :


Citation: Rhizoprionodon acutus (RÜPPELL, 1837): In: Database of modern sharks, rays and chimaeras, www.shark-references.com, World Wide Web electronic publication, Version 11/2018

Please send your images of "Rhizoprionodon acutus" to info@shark-references.com

Rhizoprionodon acutus (RÜPPELL, 1837), © Randall, J.E., www.fish-base.org
Common names
spa Cazón lechero, spa Cazón lechoso, spa Cazón picudo, spa Marajo, fra \(T\) Lézard, fra \(T\) Requin à museau pointu, fra \(T\) Requin à nez pointu, eng Blacktip shark, eng Fish shark, eng Grey dog shark, eng Grey dog-shark, eng Little blue shark, eng Longmans dogshark, eng Milk dog shark, eng Milk shark, eng Milkshark, eng Sharp nosed shark, eng Sharp-nosed milk shark, eng Walbeehm"s sharp-nosed shark, eng White-eye shark, eng Yellow dog shark, ita Squalo latteo, por Marracho branco, por Tubarão-bicudo

Short Description
Field Marks: In its area the only requiem shark with long upper and lower labial furrows, the first dorsal origin well behind the anal origin, and long preanal ridges. Key to species and diagnostic features give characters separating this from other, similar species in its genus.
Diagnostic Features: Prenarial snout 4 to 5.4% of total length; upper labial furrows long, 1.4 to 2% of total length; total count of enlarged hyomandibular pores on both sides of head just behind mouth angle usually over 16; teeth serrated in adults; teeth not well-differentiated between sexes; total tooth rows usually 25/24. First dorsal origin usually over or slightly in front of pectoral free rear tips; second dorsal origin ranges from above last third of anal base to over its insertion; pectoral anterior margin usually equal to or shorter than first dorsal length from origin to free rear tip. Posterior monospondylous precaudal centra greatly enlarged; precaudal centra usually less numerous than caudals (rarely the two are equal), precaudals 55 to 79, total centra 121 to 162. Size moderate, males maturing over 60 cm total length. Colour grey, grey-brown or purplish brown above, pale below, pectoral fins with a light margin. [517]

Distribution
Eastern Atlantic: Madeira and Mauritania to Angola; reported from the Gulf of Taranto [20075]. Indo-West Pacific: Red Sea and East Africa to Indonesia, north to Japan, south to Australia. Source: www.gbif.org

Human uses
fisheries: commercial; gamefish: yes

Biology
Distinct pairing with embrace [17086]. Viviparous, with a yolk-sac placenta; 2 to 8 in a litter [544], usually 2 to 5 after a gestation period of ~ 12 months; no seasonality in the reproductive cycle [2539]. Size at birth between 25 and 39 cm.
Diet: 2015: [22757]: Arabian Gulf waters of the United Arab Emirates (database: 57 speciemens): fed on a wide variety of teleost species, primarily Engraulidae (anchovies) (28%), Gerreidae (mojarras) (5.6%) and Carangidae (jacks) (1.6%) with occasional crustacean and cephalopod prey (8%) Occurs on the continental shelf (Ref. 75154).

Size / Weight / Age
175 cm TL (male/unsexed; [20067]); 80.8 cm TL (female); max. published weight: 5,000 g (Ref. 40637); max. reported age: 8 years [517]

Habitat
benthopelagic; amphidromous [17660]; freshwater; brackish; marine; depth range 1 - 200 m [517]

Dentition
Teeth in 13-1-13/11-1-11 series, those of both jaws with the inner border obliquely linear, the outer deeply notched (described from Scoliodon longmani = synonym of Rhizoprionodon acutus, holotype QM I.292) [11847];

Remarks
899

Parasites (arranged by Jürgen Pollerspöck)
Cestoda
  • Anthobothrium laciniatum LINTON, 1890 [16458]
  • Anthobothrium spinosum SUBHAPRADHA, 1955 [16423] [16423]
  • Balanobothrium carchariasae BHAGWAN & SHINDE, 2002 [21460]
  • Callitetrarhynchus gracilis (RUDOLPHI, 1819) PINTNER, 1931 [16112] [15730] [21816]
  • Doliobothrium musculosum (SUBHAPRADHA, 1955) [16423] [16423] [14437]
  • Hornelliella palasoorahi ZAIDI & KHAN, 1976 [16112]
  • Nybelinia dighai PRAMANIK & MANNA, 2006 [16375]
  • Nybelinia indica CHANDRA, 1986 [16112]
  • Nybelinia sp. [16112] [15730]
  • Otobothrium australe PALM, 2004 [17826]
  • Otobothrium carcharidis (SHIPLEY & HORNELL, 1906) [24083] [15730] [19555] [17826] [21816]
  • Otobothrium minutum SUBHAPRADHA, 1955 [16423] [16112]
  • Otobothrium sp. [15730]
  • Phoreiobothrium arabiansi SHINDE, JADHAV & MOHEKAR, 1984 [16167]
  • Phoreiobothrium girjamami SHINDE, MOTINGE & PARDESHI, 1993 [16405]
  • Phoreiobothrium jahki CAIRA & JENSEN, 2015 [23548]
  • Phoreiobothrium nadiae CAIRA & JENSEN, 2015 [23548]
  • Phoreiobothrium ratnagiriensis SHINDE & JADHAV, 1987 [16394]
  • Phoreiobothrium shindei SHINDE, JADHAV & JADHAV, 1990 [16243]
  • Phoreiobothrium swaki CAIRA & JENSEN, 2015 [23548]
  • Phoreiobothrium vinodae JADHAV, 1993 [16328]
  • Phyllobothrium typicum SUBHAPRADHA, 1955 [16423] [16423] [16443]
  • Platybothrium veravalensis DESHMUKH, SHINDE & JADHAV, 1977 [16300] [7384]
  • Poecilancistrium caryophyllum (DIESING, 1850) DOLLFUS, 1929 [16112]
  • Polypocephalus waltairensis MOTE, 2012 [19910]
  • Prochristianella aciculata BEVERIDGE & JUSTINE, 2010 [17404]
  • Proemotobothrium southwelli BEVERIDGE & CAMPBELL, 2001 [15730]
  • Pterobothrium acanthotruncatum ESCALANTE & CARVAJAL, 1984 [16283] [16112]
  • Tentacularia coryphaenae BOSC, 1797 [16458] [16112]

Nematoda
  • Anisakis simplex (RUDOLPHI, 1809) [21235]

Copepoda