- 10 years agoFavorite Answer
(Edit- I will not name the completely extinct classes or superclasses because Wikipedia has, in a nutshell, screwed them up.)
Traditionally (and nowadays inaccurately), all fish constituted the one class Actinopterygii. There were once five classes in the subphylum Vertebrata: Mammalia, Aves, Reptilia, Amphibia, and Actinopterygii. The first four are self explanatory. :)
However there is a headachingly massive amount of dispute among fish classification. Superclass, infraorder, subclass, etc. - each of these following groups have been classified as one or another. --__-- It is not worth explaining as every zoologist or ichthyologist is sure to disagree with the next.
So. Here are the three major distinctions among what we call 'fish'.
1. "Superclass" Agnatha: Jawless fishes. Lampreys, hagfish for example. The most primitive of fish.
2. "Class" Chondrichtyes. The sharks, rays, chimeras, and other cartilaginous, jawed fishes.
3. "Superclass" Osteichthyes. The jawed, bony fish. Largest group.
Osteichtyes is further divided into 2 important classes.
3A. Sarcopterygii. Lobe finned fish, such as lungfish and coelacanths. Most closely related to tetrapods (land creatures, and thus us humans).
3B. Actinopterygii. And here we have the 'ray finned fish', basically every other fish you can think of that is NOT lobe finned, cartilaginous, or jawless :) Angel fish, sturgeon, wrasse, guppy, you name it.
So, I hope that was not too confusing for you, and that you got the gist of it. Fish are amazingly interesting to classify, seeing as they are our closest link to invertebrates, but classification of any living thing can result in ... confusion.
I am reading a Richard Dawkins book and (I forgot who!) he put this quote from someone along the lines of, "If we try to catalogue every living plant or animal, the essence and wonder of nature and the power of evolution will be lost to the shrewd mind." Something like that.Source(s): http://www.flmnh.ufl.edu/fish/education/groupsfish... Interests in zoology and evolution (as well as aquariumkeeping(: )
- 10 years ago
Class Myxini (hagfish)
Class Pteraspidomorphi (early jawless fish)
Class Petromyzontida or Hyperoartia
Class Conodonta (conodonts)
Class Cephalaspidomorphi (early jawless fish)
Infraphylum Gnathostomata (jawed vertebrates)
Class Placodermi (armoured fish)
Class Chondrichthyes (cartilaginous fish)
Class Acanthodii (spiny sharks)
Superclass Osteichthyes (bony fish)
Class Actinopterygii (ray-finned fish)
Order Acipenseriformes (surgeons and paddlefishes)
Order Polypteriformes (reedfishes and bichirs).
Infraclass Holostei (gars and bowfins)
Infraclass Teleostei (many orders of common fish)
Class Sarcopterygii (lobe-finned fish)
Subclass Coelacanthimorpha (coelacanths)
Subclass Dipnoi (lungfish)Source(s): Marine science major! But also its on wiki!!!!
- Anonymous6 years ago
This Site Might Help You.
Name the different classes of fish ?Source(s): classes fish: https://biturl.im/QThbv
- ?Lv 710 years ago
TROPICAL FRESHWATER FISH.