The Blackspot shark (Carcharhinus sealei) is a small species of requiem shark in the family Carcharhinidae found in the tropical Indo-West Pacific Ocean. It is not a threat to humans.
Family: Carcharhinidae – Requiem sharks
Genus: Carcharhinus
Species: sealei
Phylum– Chordata
Class– Chondrichthyles
Subclass– Elasmobranchii
Common Name– Ground Sharks
Family– Carcharhinidae
Common Name– Requiem Sharks
Genus– Carcharhinus
Species– sealei
Status: IUCN Red List NEAR THREATENED
Average Size and Length: The Blackspot shark is a smaller species of shark, growing to around 37 inches long.
Teeth and Jaw: The Blackspot shark has 12 tooth rows that occur on either side of both top and bottom jaws, but the number can vary from 11 to 13. The upper teeth have strongly serrated oblique cusps and smooth-edged cusp-lets, and the lower teeth have oblique cusps, either serrated or smooth. The furrows on the upper lip are short.
Head: The snout of the Blackspot shark is fairly long, pointed or slightly rounded at the tip. The eyes are large, oval, and set horizontally, and are protected by a nictitating membrane. There are skin flaps over the nostrils.
Tail: There is no fleshy keel along the sides of the caudal peduncle. The caudal fin is about one-fifth of the total length of the Blackspot shark.
Demographic, Distribution, Habitat, Environment and Range: The Blackspot shark resides in the Indian and Pacific Oceans, on the continental shelves and shallow water around islands from the surf line to depths of about 130 feet. Research suggests that it may be intolerant of low salinity, and therefore won’t be found in estuaries or bays.
In the Indian Ocean, it is found along the east coast of Africa from South Africa and Madagascar to Kenya. It can be found around Seychelles and Mauritius, and further east, it is present around the coasts of Pakistan, India, and Sri Lanka. In the western Pacific Ocean, it is found along the coasts of Thailand, Vietnam, China, New Guinea, Indonesia, and northern and western Australia. The Blackspot shark seems to reside in South Africa, however numbers increase during summertime.
Diet: The Blackspot shark feeds on small fish, crustaceans, and squid.
Aesthetic Identification: The Blackspot shark is streamlined and slender. It is brownish or silvery grey on the dorsal surface and counter-shaded pale grey on the ventral surface, with a pale stripe running along the flank. A large, triangular black spot is on the second dorsal fin which covers at least half of the fin. The other fins have no distinctive markings, but do have pale posterior edges.
The furthest back of the five gill slits is above the origin of the pectoral fins, and no spiracles occur. The first dorsal fin is long, narrow, and falcate and has a short rear tip. It is either pointed or narrowly rounded at the apex and its origin is directly over the free posterior end of the pectoral fins. The second dorsal fin is relatively large. It also has a short rear tip and its origin is slightly behind the origin of the anal fin. The pectoral fins are falcate, long and narrow, and taper to a blunt point. the dorsal lobe is elongated and has a notch in the lower margin near the tip and the ventral lobe is smaller, markedly falcate, and has a more rounded tip.
Biology and Reproduction: Research suggest that the Blackspot shark grows rapidly and has a short lifespan. They reach maturity at about 1 year (at a length of about 28 inches), and live for about 5 years or more. The Blackspot shark is viviparous. The gestation period is about 9 months and they have 1 or 2 pups.
Off the coast of Natal, the juvenile sharks are born in spring.
Behavioral Traits, Sensing and Intelligence: Not much is known about the behavior of the Blackspot shark. There is room for a lot of research.
Blackspot Shark Future and Conservation: The Blackspot shark may be overexploited through overfishing. It is sold in local markets and its flesh is used for human consumption.
Blackspot Shark Recorded Attacks on Humans: The Blackspot shark is not a danger to humans.