Rhizoprionodon oligolinx

Grey sharpnose shark RHX
Characteristic features:

Dorsal surfaces bronze to greyish, fading to grey after death. Pectoral-fin posterior margins pale; upper lobe of caudal edged with black. Ventral surfaces white.


Maximum size up to 70 cm TL; birth size 21–26 cm TL.


Found throughout the tropical waters of the Indo–West Pacific.


Occurs on continental and insular shelves, from close inshore to at least 36 m depth.


Feeds consists of small bony fish, and also crustaceans and cephalopods. Length at maturity is 32–41 cm TL and 29–38 cm TL for females and males respectively. Reproductive mode is viviparous with yolk-sac placenta; females give birth to 3–5 pups after unknown gestation period in January and February off Mumbai in India. Maximum age is unknown.

Indonesian fisheries:

Commonly caught by inshore demersal gillnet fisheries, especially off Java. Utilised for its fins and meat, but of limited value due to its size.

Similar species:

Rhizoprionodon acutus
Milk shark

Rhizoprionodon acutus

Rhizoprionodon acutus differs in having very long and prominent upper labial furrows (vs. very short).

Rhizoprionodon taylori
Australian sharpnose shark

Rhizoprionodon taylori

Rhizoprionodon taylori differs in having 7–16 enlarged pores in total near mouth corners (vs. 15–22 enlarged pores near mouth corners).

Negaprion acutidens
Sicklefin lemon shark

Negaprion acutidens

Negaprion acutidens differs in having second dorsal fin nearly as large as first dorsal fin (vs. second dorsal fin much smaller than first dorsal fin) and snout broadly rounded, when viewed from underneath (vs. pointed).

Loxodon macrorhinus
Sliteye shark

Loxodon macrorhinus differs in having a posterior notch on eyes (vs. no posterior notches present); second dorsal fin and anal fin similarly sized (vs. anal fin much larger than second dorsal fin) and an anal-fin posterior margin deeply notched (vs. almost straight).

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