Scoliodon Dogfish characters

 Scoliodon Dogfish

Classification of Scolidon also known as Dogfish.

Systemic Position of Scoliodon
Phylum	Chordate
Subphylum	Vertebrata
Division	Gnathostomata
Superclass	Pisces
Order	Squaliformes
Family	Carcharinidae
Genus	Scoliodon (Dogfish)
Species	S. sorrakowah

Geographical distribution of Scoliodon

Scoliodon has a wide distribution. About 4 species are found all along the Indian sea coast. Its presence has been reported from Zanzibar, Srilanka to Malay Archipelago, East Indies, Philippine Islands, Mexico to Panama, Cuba, West Indies, and South America. Lower Carboniferous to Recent.

Habit and habitat of Scoliodon 

The natural home of Scoliodon is the sea, but some live in estuaries and even ascend the rivers. They are predacious active swimmers and voracious feeders attacking their prey with their powerful jaws.

Comments on Scoliodon

(1) Commonly called dogfish or dog shark, approximately 60 cm long. 

(2) Spindle-shaped body, divided into head, trunk, and tail.

(3) Dorsal and lateral sides of the body are pigmented dark grey or slaty grey, while the ventral side is white.

(4) Head dorso-ventrally compressed and flattened into snout having ventrally slit-like mouth, obliquely situated nostrils, and laterally situated protuberant eyes. A little behind the eyes are five pairs of lateral gill clefts.

(5) Trunk bears paired fins. Dorsally there are a 1st dorsal fin, 2nd dorsal fin, and a dorsal caudal pit. Ventrally anterior pectoral fins, paired posterior pelvic fins.

(6) Heterocercal tail turned upwards and caudal fin with upper epicardial and lower hypochondria lobes. 

Labeled diagram of Scoliodon

(7) A pair of pigmented lateral lines extends from head to tail. 

(8) Scollodon exhibits sexual dimorphism. Males are easily recognized by having a pair of intromittent organs, called claspers. Cloaca between 2 pelvic fins.

Economic importance of Scoliodon 

Scoliodon has great educational and experimental value because of its availability and size and is a very favorite dissection fish for both undergraduate and postgraduate students. Special features: Sharks are used as human food in many countries. Shark fins are dried and then boiled to yield a gelatinous substance favored for soups. The tanned shark skin shagreen is used to case fine books, jewel boxes, sword handles, etc. Sharks are a nuisance to fishermen, because they tear nets, steal captured fish, and take out bait or fish from hooks. Identification: Since the animal has raised tail, pointed snout, and above features, hence it is Scoliodon.

Natural History Scoliodon

Skeleton is made of cartilage. Most sharks and rays are marine, but a few live in tropical rivers above salt water. Sharks live in open water, and rays on the bottom. The sharks are predaceous, active swimmers and feed on small fishes. Sharks and rays are used as human food in many countries. Shark liver contains much oil rich in vitamin A.

Sharks are also a nuisance to fishermen because they tear nets and steal captured fish. Large sharks may capsize small boats and injure or kill fishermen. Living fishes probably exceed 20,000 species, an abundance, and diversity unequaled among all other vertebrates. They originated 530 million years ago allowing a vast span of time for evolutionary divergence and for the origin and extinction of major phyletic lines.

Questions on Scoliodon Dogfish 

Q. What are some common names for Scoliodon?

Ans.- Scoliodon is commonly called dogfish or dog shark.

Q. How is the body of Scoliodon structured?

Ans.- The body of Scoliodon is spindle-shaped and divided into head, trunk, and tail.

Q. What is the coloration pattern of Scoliodon?

Ans.- The dorsal and lateral sides of the body are pigmented dark grey or slaty grey, while the ventral side is white.

Q. Describe the features of Scoliodon's head.

Ans.- The head of Scoliodon is dorso-ventrally compressed and flattened into a snout. It has a ventrally slit-like mouth, obliquely situated nostrils, and laterally situated protuberant eyes. A little behind the eyes are five pairs of lateral gill clefts.

Q. Which fins are present on the trunk of Scoliodon?

Ans.- The trunk of Scoliodon bears paired fins, including the 1st dorsal fin, 2nd dorsal fin, and a dorsal caudal pit. It also has ventrally anterior pectoral fins and paired posterior pelvic fins.

Q. What is the shape of Scoliodon's tail and caudal fin?

Ans.- Scoliodon has a heterocercal tail turned upwards and a caudal fin with upper epicardial and lower hypochondria lobes.

Q. What is the significance of the lateral lines in Scoliodon?

Ans.- A pair of pigmented lateral lines extends from the head to the tail of Scoliodon.

Q. How can males of Scoliodon be distinguished?

Ans.- Male Scoliodon exhibit sexual dimorphism and can be recognized by having a pair of intromittent organs called claspers. The cloaca is situated between the two pelvic fins.

Q. What is the economic importance of Scoliodon?

Ans.- Scoliodon has great educational and experimental value, making it a popular choice for dissection among undergraduate and postgraduate students. Shark fins are dried and boiled to yield gelatinous substances used in soups. The tanned shark skin is used for various purposes such as casing fine books, jewel boxes, and sword handles. However, sharks can also be a nuisance to fishermen.

Q. What type of environment do sharks and rays usually inhabit?

Ans.- Most sharks and rays are marine, although a few live in tropical rivers above saltwater. Sharks live in open water, while rays are found on the bottom.