1. extinct group of armored jawless fishes or fish-like vertebrate; taxonomy is not clear; [syn: Heterostraci, suborder Heterostraci]
WordNet (r) 3.0 (2006):
suborder Heterostraci
n 1: extinct group of armored jawless fishes or fish-like
vertebrate; taxonomy is not clear [syn: Heterostraci,
suborder Heterostraci]