Classification:

• Class- Chordata
• Phylum- Amphibia
• Order- Urodela
• Genus- Necturus

Comments:

1. 1. Necturus is an aquatic salamander of rivers and lakes found crawling on the bottom. It feeds on invertebrates and small fishes.
2. 2. Necturus is known as mud puppy or water dog.
3. 3. Body is elongated, measuring 30-42 cm in length.
4. 4. The general colour of the body is rusty brown with blackish spots.
5. 5. Head bears small lidless eyes , nostrils, and mouth.
6. 6. Lungs are present.
7. 7. Attempts have been made to force Necturus to undergo metamorphosis but no success has been achieved.
8. 8. Necturus is found in rivers of North America and Yugoslavia.
9. 9. It is a typical permanent neotenic larva and exhibits following larval characters-
10. Three pairs of external gills and two pairs of gill clefts are present in the adult.
11. Skull largely cartilaginous.
12. Musculature larval.
13. Larval circulatory system.
14. Lateral line organs are present and Jacobs organ absent.

Source:

1. Practical Zoology Vertebrates by S.S.Lal. 2. A Manual of Practical Zoology Chordates by Dr. P.S. Verma.