ostracoderm
noun
ä-ˈstra-kə-\
Definition of ostracoderm
: any of various primitive, extinct jawless fish (class Agnatha) of the Lower Paleozoic with a bony covering of plates or scales serving as a protective armor and which on the broad head usually form a bony shield of fused plates
Note:
Distant relatives of the hagfish and lampreys, ostracoderms were typically less than 12 inches (30.5 centimeters) long. Unlike earlier vertebrates using the gills for both feeding and breathing, ostracoderms were the first known forms to use the gills exclusively for respiration.
Keep scrolling for more
Comments on ostracoderm
What made you want to look up ostracoderm? Please tell us where you read or heard it (including the quote, if possible).
Test Your Vocabulary
Words from Greek and Roman Mythology Quiz
-
- Boreal comes from the name of the ancient Greek god of which wind?
Can you spell these 10 commonly misspelled words?
TAKE THE QUIZ
Test Your Knowledge - and learn some interesting things along the way.
TAKE THE QUIZ
Share ostracoderm
Resources for ostracoderm