A New Perleidiform(Actinopterygii,Osteichthyes)from the Middle Anisian(Middle Triassic)of Yunnan,Sou

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Two complete specimens from the Pelsonian(Middle Anisian,Middle Triassic)of Luoping, Yunnan Province,South China are referred to a new actinopterygian genus,Luopingichthys gen.nov.,and ascribed to the perleidiform family Polzbergidae based especially on a typical synapomorphy of a peculiar premaxillary-maxillary complex,i.e.,the fusion between premaxillary and maxillary along the antero-dorsal margin of the maxillary.The new taxon differs from other deep-bodied representatives of the family,Felberia and Stoppania,in its fusiform or deep fusiform body shape; sickle-shaped preopercular with short infraorbital process;lack of modified scales at the base of the anal fin;the short-based dorsal fin;scarcely ornamented scales;and thin anterior teeth.Based on a redescription of the holotype of the taxon Ctenognathichthys hattichi from the Middle Triassic (Ladinian)Prosanto Formation,Canton Graubiinden,eastern Switzerland,the only known specimen, which shows the same fusion between premaxillary and maxillary,the systematic position of the species is clarified and the taxon is proposed to be a further representative of the family Polzbergidae,and is transferred to the new genus.
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