2001, "Axial Skeleton", David Cannatella, https://web.archive.org/web/20051222184337/http://www.lifesci.utexas.edu/courses/bio478L/LecturesPDF/bodyskeleton.pdf "Some bony fishes (Teleostei, Amia, Lepisosteus, and Brachiopterygii) have well-ossified centra and neural and hemal arches. Others (Dipnoi, Latimeria, and Chondrostei) lack centra (acentrous), and the notochord is unconstricted, and the bony neural and hemal arches simply rest on it."
Source: wiktionary