Devonian fish

Source: Wikipedia. Pages: 49. Chapters: Thelodonti, Onychodus, Tiktaalik, Dunkleosteus, Psarolepis, Gogonasus, Marsdenichthys, Eusthenopteron, Panderichthys, Elpistostegalia, Galeaspida, Cladoselache, Eastmanosteus, Materpiscis, Styloichthys, Anaspida, Edaphodon, Cheirolepis, Cephalaspis, Rhenanida, Bothriolepis, Deinodus, Hyneria, Xenacanthus, Ventastega, Ostracoderm, Stethacanthus, Ctenurella, Osteostraci, Gooloogongia, Titanichthys, Coccosteus, Tristichopteridae, Stensioella, Gemuendina stuertzi, Mandageria, Errivaspis, Pteraspis, Mcnamaraspis kaprios, Doryaspis, Osteolepis, Pterichthyodes, Climatius, Brindabellaspis, Porolepiformes, Campbellodus, Groenlandaspis, Dipterus, Diplocercides, Diabolepis, Ichnomylax, Bradyodonti, Strunius, Jagorina, Hemicyclaspis, Dipnorhynchus, Holoptychius, Xeradipterus, Bukkanodus, Endeiolepis, Drepanaspis gemuendenensis, Soederberghia, Lunaspis, Ateleaspis, Kenichthys, Phyllolepis, Boreaspis, Benneviaspidida, Psammosteidae, Qingmenodus, Rolfosteus canningensis, Phlyctaeniidae, Pteraspidomorphi, Carolowilhelmina, Elpistostege, Austroptyctodus, Gyroptychius, Lepidaspis, Plourdosteus, Langlieria, Chondrenchelys, Heddleichthys, Chrysolepis, Turrisaspis, Moythomasia, Cheiracanthus, Canowindra, Griphognathus, Dipteridae, Meemannia, Ischnacanthus, Eoactinistia, Melanognathus, Parexus, Livoniana, Beelarongia, Duffichthys, Notorhizodon, Cabonnichthys, Canowindridae, Uranolophidae, Jarvikina, Pycnosteus, Youngolepis, Ctenaspis, Rhynchodipteridae, Aleosteus, Dipnorhynchidae, Platycephalichthys, Uranolophus, Luckeus, Miguashaia, Nostolepis, Stomiahykidae, Osteolepidae, Grossius, Eusthenodon, Neophlyctaenius, Uranolophina, Holoptychiidae, Diplocercidae, Actinolepidae, Miguashaiidae, Chirodipterus, Dicksonosteus, Tristichopterus, Achoania, Cometicercus, Quebecius, Arctolepis, Dictyonosteus, Cornuata, Mithakaspis, Canningius, Bogdanovia, Birkenia, Heterogaspis, Chirodipteridae, Tiaraspis, Barwickia, Amadeodipterus, Huginaspis, Chagrinia, Heintzosteus, Fleurantia, Arctaspis, Gavinaspis, Kueichowlepis, Pageauaspis, Panderichthyidae, Nielsenia, Rhachiosteus, Grossipterus, Andreyeichthys, Rhynchodipterus, Elegantaspis, Rhamphodopsis, Cartieraspis, Gaspeaspis, Prosphymaspis, Kolpaspis, Diadsomaspis, Aggeraspis, Powichthys, Jarvikia, Sauripterus, Dipteroides, Stomiakykus, Conchodus, Koharolepis, Ganorhynchus, Mesacanthus, Archaeonectes, Glyptolepis, Holdenius, Tesseraspis, Minicrania. Excerpt: Thelodonts (from Greek: "nipple teeth") are a group of small, extinct jawless fishes with distinctive scales instead of large plates of armor. There is much debate over whether the group of Palaeozoic fish known as the Thelodonti (formerly coelolepids) represent a monophyletic grouping, or disparate stem groups to the major lines of jawless and jawed fish. Thelodonts are united in possession of "thelodont scales". This defining character is not necessarily a result of shared ancestry, as it may have been evolved independently by different groups. Thus the thelodonts are generally thought to represent a polyphyletic group, although there is no firm agreement on this point; if they are monophyletic, there is no firm evidence on what their ancestral state was. "Thelodonts" were morphologically very similar, and probably closely related, to fish of the classes Heterostraci and Anaspida, differing mainly in their covering of distinctive, small, spiny scales. These scales were easily dispersed after death; their small size and resilience m...