Scientific Name: Petromyzon sp.
Classification
Phylum: Chordata -Dorsal tubular nerve cord, gill-slits and notochord present.
Subphylum: Vertebarata -Vertebral column present.
Superclass: Agnatha -Jaws and paired appendages absent.
Class: Cyclostomata -Mouth circular, suctorial, without jaws.
Order: Petromyzontia -Mouth with a funnel, without tentacles. Nasopharyngeal pouch blind. Gills 7 pairs, open independently to the exterior. The branchial basket is well developed.
Genus: Petromyzon
Habit and Habitat: Petromyzon is found both in salt and fresh water. They lead an ectoparasitic life on other fishes, attaching to the body of the host by buccal funnel and secreting an anticoagulant for continuous flow of blood. They are also anadromous i.e., ascending rivers for spawning.
Characteristics
- The body is eel-like, measuring about 90 cm, and differentiated into head, trunk and tail. The first dorsal fin, second dorsal fin and caudal fin confluent.
- Skin is without scales, slimy, green, brown and with a strong metallic lustre.
- The Head contains a mouth but no jaws. The mouth is surrounded by a large, ventral, suctorial funnel with numerous horny teeth. The 'tongue' is toothed and piston-like.
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