Biology:Panxiosteus

Short description: Extinct genus of fishes

Panxiosteus Temporal range: Middle Devonian: Givetian, 387.7–382.7 Ma PreЄ Є O S D C P T J K Pg N ↓
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	†Placodermi
Order:	†Arthrodira
Suborder:	†Brachythoraci
Family:	†Panxiosteidae
Genus:	†Panxiosteus Wang, 1979
Type species
Panxiosteus oculus Wang, 1979

Panxiosteus is an extinct monospecific genus of placoderm arthrodire from the Middle Devonian: Givetian stage of Yunnan province, China .

Phylogeny

Panxiosteus is a member of Panxiosteidae. In the 2010 Carr & Hlavin phylogenetic study, Panxiosteidae was recognized as the sister taxon to the family Dunkleosteidae, which together comprised the superfamily Dunkleosteoidea (one of the three major clades of Eubrachythoraci). The phylogeny of Panxiosteus within Panxiosteidae is shown in the cladogram below from the 2013 Zhu & Zhu study:

Eubrachythoraci	Coccosteomorphi   Coccosteus cuspidatus       Harrytoombsia elegans       Mcnamaraspis kaprios   Incisoscutoidea   Compagopiscis croucheri       Incisoscutum ritchiei     Incisoscutum sarahae     Camuropiscidae   Latocamurus coulthardi     Camuropiscis laidlawi       Rolfosteus canningensis     Tubonasus lennardensis     Fallacosteus turneri               Aspinothoracidi   Dinichthys herzeri       Hadrosteus rapax       Gorgonichthys clarki       Heintzichthys gouldii   Selenosteidae   Stenosteus angustopectus       Gymnotrachelus hydei       Rhinosteus parvulus     Pachyosteus bulla                   Dunkleosteoidea   Westralichthys uwagedensis         Protitanichthys rockportensis   Panxiosteidae   Panxiosteus ocullus     Janiosteus timanicus     Plourdosteus canadensis       Dunkleosteidae     Eastmanosteus calliaspis     Xiangshuiosteus wui         Eastmanosteus pustulosus     Kiangyousteus yohii     Golshanichthys asiatica       Dunkleosteus amblyodoratus     Dunkleosteus terrelli     Dunkleosteus raveri

However, the subsequent 2016 Zhu et al. study using a larger morphological dataset recovered Panxiosteidae well outside of Dunkleosteoidea, instead within Coccosteomorphi and then Coccosteoidea as the sister group of Coccosteidae, as shown in the cladogram below:

Eubrachythoraci

Coccosteomorphi Coccosteoidea Coccosteidae     Millerosteus minor     Coccosteus cuspidatus         Dickosteus threiplandi     Watsonosteus fletti     Protitanichthys rockportensis       Panxiosteidae   Plourdosteus canadensis     Panxiosteus ocullus     Janiosteus timanicus       Incisoscutoidea   Harrytoombsia elegans       Torosteus tuberculatus     Torosteus pulchellus         Mcnamaraspis kaprios       Compagopiscis croucheri     Trematosteus fontanellus   Camuropiscidae     Incisoscutum ritchiei     Incisoscutum sarahae         Rolfosteus canningensis       Tubonasus lennardensis       Fallacosteus turneri       Camuropiscis laidlawi     Latocamurus coulthardi                     Pachyosteomorphi   Rhachiosteus pterygiatus     Dunkleosteoidea   Eastmanosteus calliaspis         Eastmanosteus pustulosus     Kiangyousteus yohii         Golshanichthys asiatica       Westralichthys uwagedensis         Dunkleosteus raveri     Dunkleosteus terrelli         Dunkleosteus amblyodoratus   Heterostiidae   Heterosteus ingens     Yinosteus major                 Aspinothoracidi   Tapinosteus heintzi         Bullerichthys fascidens       Kendrickichthys cavernosus     Bruntonichthys multidens           Dinichthys herzeri       Hadrosteus rapax       Gorgonichthys clarki   Selenosteidae   Heintzichthys gouldii     Pachyosteus bulla     Gymnotrachelus hydei     Stenosteus angustopectus     Brachyosteus dietrichi       Melanosteus occitanus     Rhinosteus parvulus

References

Wikidata ☰ Q112262163 entry