Which of the following is a group of primitive vertebrates having a large jawless
sucking mouth, no limbs or paired fins and a completely cartilaginous skeleton with a persistent notochord?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. Cyclostomata.
- Cyclostomata is a group of chordates that comprises the living jawless fishes: the lampreys and hagfishes.
- They are very small, and most species are less than 10 cm long.
- Cyclostomes are primitively jawless fishes that possess a single nostril on the top of their heads, and a simple, sucking mouth.
- They have no scales, and their skin is smooth.