The Hardnose shark (Carcharhinus macloti) is a species of requiem shark, in the family Carcharhinidae. It is found in the Indo-Pacific. The Hardnose shark is small and bronze and gets its name from the calcified cartilage in and around its snout.
Family: Carcharhinidae – Requiem sharks
Genus: Carcharhinus
Species: macloti
Phylum– Chordata
Class– Chondrichthyles
Subclass– Elasmobranchii
Common Name– Ground Sharks
Family– Carcharhinidae
Common Name– Requiem Sharks
Genus– Carcharhinus
Species– macloti
Status: IUCN Red List NEAR THREATENED
Average Size and Length: The Hardnose shark is known to reach 3.6 feet in length.
Teeth and Jaw: The Hardnose shark has an arched mouth with inconspicuous furrows at the corners. Some researchers suggest that the hyomandibular pores are enlarged, and some disagree with this statement. The upper teeth of the Hardnose shark number 29–32 rows and have a narrow, smooth-edged central cusp with very coarse serrations at the base on either side. The lower teeth number 26–29 rows and are narrow and smooth-edged.
Head: The Hardnose shark has a long, narrow pointed snout with large and circular eyes with nictitating membranes. The Hardnose shark gets its name because its rostral (snout) cartilages are highly calcified. The nostrils have skin flaps.
Denticles: The skin is covered by overlapping, oval-shaped dermal denticles that has 3 horizontal ridges leading to marginal teeth.
Tail: The caudal fin has a well-developed lower lobe and a longer upper lobe with a ventral notch near the tip. A prominent notch is present on the caudal peduncle at the dorsal origin of the caudal fin.
Demographic, Distribution, Habitat, Environment and Range: The Hardnose shark is common and widely distributed in the tropical western Indo-Pacific. It can be found from Kenya to Myanmar in the Indian Ocean, including Sri Lanka and the Andaman Islands. In the Pacific Ocean, it is found from Vietnam to Taiwan and southern Japan, in Indonesia, and off New Guinea and northern Australia.
The Hardnose shark is usually found in shallow, inshore waters, but has been reported to a depth of 560 feet. Tagging data has shown that this shark tends not to make long-distance movements, with 30% of re-caught individuals having moved less than 30 miles from their initial tagging location. The longest known distance travelled by a Hardnose shark is 442 miles.
Diet: The Hardnose shark mostly eats bony fish but will also eat cephalopods and crustaceans.
Aesthetic Identification: The Hardnose shark has a slim body, with five pairs of short gill slits. It is bronze above and counter-shaded white below, with a barely noticeable pale band on the flanks. The pectoral, pelvic, and anal fins sometimes have lighter margins, while the first dorsal fin and upper caudal fin lobe may have darker margins.
The pectoral fins of the Hardnose shark are fairly short and pointed, with a falcate shape. The first dorsal fin is medium-sized and triangular, and originates roughly over the pectoral fin free rear tips. The second dorsal fin is small and low, and originates over the middle of the anal fin base. Both dorsal fins have very long free rear tips, and there is a subtle midline ridge between them.
Biology and Reproduction: Parasites of the Hardnose shark are the nematode Acanthocheilus rotundatus and the tapeworm Otobothrium carcharidis.
The Hardnose shark is viviparous. Females give birth once every other year to 1 or 2 pups following a gestation period of 12 months. Newborns measure 18–22 inches long. They reach sexual maturity at 28–30 inches long. The maximum recorded lifespan of a Hardnose shark is at least 15–20 years.
Behavioral Traits, Sensing and Intelligence: The Hardnose shark forms large groups, often associating with Spottail sharks and Australian Blacktip sharks. Males and females generally travel separately from one another.
Hardnose Shark Future and Conservation: The Hardnose shark is caught with gillnets and line gear by commercial fisheries across much of its range. It is used for meat, which is sold fresh or dried and salted, though its small size limits its economic importance. It has a low reproductive rate and therefore is considered at risk, however in some regions it is still of least concern.
Hardnose Shark Recorded Attacks on Humans: The Hardnose shark is considered harmless to humans.