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Glite Dictionary
ostracoderm

ostracoderm

9.9
A fish without jaws that had heavy bony armor and lived long ago
  • noun
  • /ˈɑstrəˌkoʊdərm/
  • Specialized
translation icon : ostracodermo
  • Fossils of the ostracoderm reveal the presence of bony armor over most of its body.

Examples

  • Scientists believe that the extinction of the ostracoderm marked a major turning point in vertebrate evolution.

  • The museum's exhibit includes a reconstructed model of an ancient ostracoderm.

  • The ostracoderm was an important species in the Paleozoic Era.

  • Did you know that ostracoderms lived over 400 million years ago?

  • Fossils of ostracoderms reveal their heavily armored bodies, which provided protection from predators in ancient oceans.

  • Scientists study ostracoderms to learn about the evolution of vertebrates during the Paleozoic Era.

  • The discovery of ostracoderms in sedimentary rocks gives researchers insight into early fish-like organisms.

Synonyms

Ostracodermi
vsostracoderm
  • Specialized
9.9

An extinct group of jawless animals with heavy bony shields from long ago

is the same group but referred to with a different form of the name
Osteostraci
vsostracoderm
  • Specialized
9.9

An extinct group of armored, jawless fish that lived a long time ago

is broader, covering various heavily armored jawless vertebrates
Heterostraci
vsostracoderm
  • Specialized
9.9

A group of armored jawless fish that lived in ancient seas and are now extinct

is the more general label that includes this and other armored groups
suborder Heterostraci
vsostracoderm
  • Specialized
9.9

Fish with hard plates and no jaws known from fossils that lived a very long time ago

is the wider category that encompasses such subgroups
Cephalaspida
vsostracoderm
  • Specialized
9.9

An extinct group of early fish with bony head shields

is more general, including heavy armor beyond just head shields
heterostracan
vsostracoderm
  • Specialized
9.9

An extinct jawless fish with bony plates on its head and front body that lived in the sea

is the collective category rather than one specific fish
osteostracan
vsostracoderm
  • Specialized
9.9

An extinct jawless fish with a heavy armored head from the Devonian period

is broader, not limited to Devonian examples or head shields only
cephalaspid
vsostracoderm
  • Specialized
9.9

A jawless fossil fish from the Devonian with a hard shield on its head

is the larger group containing many genera rather than one genus
anaspid
vsostracoderm
  • Specialized
9.9

A small extinct freshwater fish without jaws that lived long ago and had a bony head

emphasizes full heavy body armor rather than limited head plating
Anaspida
vsostracoderm
  • Specialized
9.9

An extinct group of jawless fish with no bony plates that lived long ago

focuses on heavily armored body forms instead of shieldless types
order Anaspida
vsostracoderm
  • Specialized
9.9

An extinct group of jawless fish that lived hundreds of millions of years ago

is specific to heavily armored jawless vertebrates rather than all orders

Surface Forms

ostracoderm singular
ostracoderms plural

Morphology

ostracoderm = ostraco + derm

Formed from Greek combining elements ('ostraco-' and '-derm') that are not standalone English words, so an average B1 learner cannot derive the meaning from familiar English bases.

Etymology

Ostracoderm comes from the Greek parts ostraco- meaning 'shell' and -derm meaning 'skin', so it literally means 'shell-skin'. That's why ostracoderm is used for the ancient jawless fish that had heavy bony plates like armor over their bodies.