Assertion: small jawless armored fish | /r/HasProperty | ostracoderm
Facets:
Source sentences:
text: Among vertebrates, jawless armoured fish (ostracoderms) declined in diversity, while the jawed fish (gnathostomes) simultaneously increased in both the sea and fresh water.
text: Early fish from the fossil record are represented by a group of small, jawless, armored fish known as ostracoderms.