What is another word for heterostraci?
Pronunciation: [hˈɛtɹə͡ʊstɹˌasa͡ɪ] (IPA) 
Heterostraci is a term used to classify a group of extinct, armored fish that lived during the Devonian period. Synonyms for heterostraci include heterostracans, armored jawless fish, and ostracoderms. The term "ostracoderm" is often used to describe a broader group of extinct, heavily armored fish that lacked jaws, and includes both the heterostraci and anaspids. Heterostracans are known for their distinctive armor plating and ranged in size from just a few centimeters to over a meter in length. These ancient fish are important in the study of early vertebrate evolution and provide insight into the emergence and diversification of jawed vertebrates.
