Noun: heterostracan ,he-tu'ró-stru-kun
- Extinct jawless fish with the anterior part of the body covered with bony plates; of the Silurian and Devonian
"Heterostracans were among the earliest armoured vertebrates"
Derived forms: heterostracans
Type of: agnathan, jawless fish, jawless vertebrate
Part of: Heterostraci, suborder Heterostraci
Encyclopedia: Heterostracan