Table of Contents
Scoliodon: A Cartilaginous Fish:
Scoliodon is a cartilaginous fish, they are aquatic, the body is streamlined, the body is covered by scales(dermal denticles), they are all marine. Scoliodon is a true fish, all the fishes can be classified into two categories based on their endoskeleton, cartilaginous fish and bony fish.
All the cartilaginous fish are placed under the class Chondrichthyes, under the class Chondrichthyes rays, sharks, skates, chimeras. When we try to learn about the cartilaginous fishes we first learn about sharks, we generally study the Dogfish shark, the Scoliodon. Cartilaginous fish are also known as elasmobranchs, common Indian Dogfish shark is Scoliodon sorrakowah, there are some important reasons why Dogfish shark is studied worldwide —
- For Indian students, common Indian Dogfish is very useful because it is available in Indian Ocean.
- In Dogfish the endosketon is made of cartilage, bone absent so it is very easy to dissect for the study of internal anatomy.
- The size of Dogfish is not very large nor very small so we can easily dissect them in laboratory.
- Almost all the features of cartilaginous fish are present in Scoliodon, so if we study Scoliodon then it is possible to get the general ideas about all the features of cartilaginous fishes.
- Basic anatomy of advanced Vertebrate is present in Scoliodon so study of Scoliodon help us to understand the basic anatomy of Vertebrate.
- The features present in Scoliodon is present in embryonic stage of higher Vertebrate which indicates that relationship of Scoliodon with higher Vertebrate.
Geographical Distribution of Scoliodon:
Scoliodon available in the Indian Ocean, Atlantic Ocean, the eastern coast of South America, Pacific Ocean, Scoliodon sorrakowah, Scoliodon palasorrah, Scoliodon dumarilli, Scoliodon walbeehmii are present in India in large numbers. The common Indian Dogfish is Scoliodon sorrakowah, it has a special meaning, the Sora term represents ‘shark’ and the kowah term represents ‘black’, in South India it is known as ‘black shark’.
Habit and Habitat of Scoliodon:
Scoliodon is a marine cartilaginous fish, they feed on other small fishes, crabs, lobster, worms, Scoliodon is a very efficient predator. Scoliodon has an elongated snout, the body is compressed, the teeth present on the upper jaw and lower jaw are similar. Dogfish have great swiftness in swimming, they chase the prey and catch their prey with their sharp teeth.
Male and female sharks are separate, fertilization occurs internally and the development is indirect, the adult shark gives birth to the young ones without involving in any larval stage. The embryo develops inside the uterus of an adult shark, the Dogfish is viviparous.
Systematic Position of Scoliodon:
All the Chordate features are present in Scoliodon so we place Scoliodon under phylum Chordata. Under phylum Chordata Scoliodon present in the Subphylum Vertebrata, all Vertebrate features like the skull, the vertebral column is present in Scoliodon. Under Subphylum Vertebrata they are placed under division Gnathostomata, the presence of jaw separate them from the primitive fish like Vertebrate.
Superclass Pieces is a category under the group Gnathostomata, in superclass Pieces, we place all the fish in which fin present as external appendages, in Scoliodon the appendages are paired fin. Under superclass Pieces, we have two types of fish, cartilaginous fish, and bony fish, bony fishes are placed under the class Osteichthyes, and Cartilaginous Fish are placed under the class Chondrichthyes.
Scoliodon has a cartilaginous endoskeletal, so we placed them under the class Chondrichthyes, under subclass Chondricthys, we place Scoliodon in subclass Selachi, under subclass Selachi we placed them in the order Squaliformes.
Scoliodon belongs to the family Carcharinidae, and the genus name is Scoliodon, Scoliodon also known as Dogfish, the common Indian Dogfish is Scoliodon sorrakowah, this species of Scoliodon also known as the black shark in South India.
Detailed Study On
Biological Significance of Placodermi
Characteristics Features of Placodermi
Hi Everyone!!! Welcome to Imaluop. Imaluop always try to learn some new and he want to share to other people. Here we will try to learn various topics on Science, specially on Biological Sciences.
