agnathan
(noun)
a member of the superclass Agnatha of jawless vertebrates
Examples of agnathan in the following topics:
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Agnathans: Jawless Fishes
- Jawless fishes or agnathans are craniates that represent an ancient vertebrate lineage that arose over one half-billion years ago.
- "Gnathos" is Greek for "jaw" and the prefix "a" means "without," so agnathans are "without jaws. " Most agnathans are now extinct, but two branches still exist today: hagfishes and lampreys.
- A defining feature of agnathans is the lack of paired lateral appendages or fins.
- These agnathans are classified as Myxini and do not have a vertebral column.
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Gnathostomes: Jawed Fishes
- In early evolutionary history, there were gnathostomes (jawed fishes) and agnathans (jawless fishes).