Definition of Acanthodii. Meaning of Acanthodii. Synonyms of Acanthodii

- Acanthodii or acanthodians is an extinct class of gnathostomes (jawed fishes). They are currently considered to represent a paraphyletic grade of various...
- Olfactores Subphylum: Vertebrata Groups included "Agnatha" †"Placodermi" †"Acanthodii" Chondrichthyes Osteichthyes Actinopterygii Sarcopterygii (including tetrapods)...
- animals not in it. The only extinct classes shown are Placodermi and Acanthodii. Note that there are many other extinct chordate groups that are not shown...
- relatives) class †"Placodermi" (armoured fish, paraphyletic) class †"Acanthodii" ("spiny sharks", sometimes classified under Actinopterygii and paraphyletic)...
- extinct (armored gnathostomes) └Eugnathostomata (true jawed vertebrates) ├─Acanthodii (stem cartilaginous fish) └─Chondrichthyes (true cartilaginous fish) ├─Holocephali...
- these, there are two classes of extinct armoured fishes, Placodermi and Acanthodii, both paraphyletic. Other ways of classifying the vertebrates have been...
- Females attain a larger size than males. The largest of the now-extinct Acanthodii was Xylacanthus grandis, an ischnacanthiform based on a ~35 cm (14 in)...
- gnathostomes) class Chondrichthyes (cartilaginous fish; 900+ species) class †"Acanthodii" (Paleozoic "spiny sharks"; paraphyletic in relation to Chondrichthyes)...
- fish known as placoderms, which evolved from the ostracoderms; and the Acanthodii (or spiny sharks). The jawed fish that are still extant in modern days...
- Tetanopsyrus is a genus of Acanthodii. There are two species of this genus that lived through the lower Devonian (Lochkovian), some 416 to 359 million...