NOUN
- extinct fish-like jawless vertebrate having a heavily armored body; of the Paleozoic
How To Use ostracoderm In A Sentence
- Enamel, or enameloid tissue covering tubercles, was clearly described in Ordovician vertebrates such as the ostracoderms.
- During this period the agnathan and gnathostome fishes, too, gave rise to many distinctive groups: the armoured ostracoderm and placoderms, the bony fishes, and elasmobranchs to populate marine and freshwater environments.
- [[ostracoderm]] s jawless fish related to present-day [[lamprey]] s and Conservapedia - Recent changes [en]
- With their armored head shield and trunk shield composed of overlapping bony plates, the placoderms appear at first glance extremely similar to the ostracoderms (armoured jawless fish).
- With their armored head shield and trunk shield composed of overlapping bony plates, the placoderms appear at first glance extremely similar to the ostracoderms (armoured jawless fish).
- The oldest fossil related to all modern vertebrates, the ostracoderm a jawless, bony-plated fish, dates to about 490 million years ago. Trout and Salmon of North America
- [[ostracoderm]] s jawless fish related to present-day [[lamprey]] Conservapedia - Recent changes [en]
- By the Middle Devonian the armoured jawless ostracoderms were in decline, and instead the jawed fish were undergoing a great evolutionary radiation in both the sea and in freshwater.
- These were jawless, armored fish informally called ostracoderms, but more correctly placed in the taxon Pteraspidomorphi.
- If lancelets and the fossil ostracoderms are considered out-groups to living craniates, then the brains of the earliest craniates must have been very small for their body size.
