The suborder Protomecoptera was erected by Tillyard in 1917 from Australian Late Triassic strata. However, Carpenter (1992) considered that Protomecoptera might belong to the suborder Eumecoptera. Recently two new fossil genera,Glyptochorista martynovae gen. et sp. nov. and Phyllochorista orientis gen. et sp. nov., have been discovered by the author for the first time in the Middle Triassic Tongchuan Formation of Shaanxi Province, China, and are assigned to the family Tomiochoristidae O. Martynova, 1958 of this suborder. Thus the family Tomiochoristidae is stratigraphically extended to the highest horizon, i.e. from the Early Permian to Middle Triassic, spanning more than 50 Ma. The discovery of thenew genera and species in China fills in the gaps in the field of protomecopterid of China and so has certain reference value for the study of the evolution of this family (Tomiochoristidae) from the Late Paleozoic to Early Mesozoic. The fossils were collected from grayish green mudstone-shale in the upper part of the Lower Member of the Middle Triassic Tongchuan Formation in Tongchuan. The new genera and new species are a new member of the Tongchuan Entomassemblage of the Shaanxi Entomofauna (a fossil group of the Mid Triassic Shaanxi fauna or Shaanxi biota) and their age is equivalent to the Ladinian stage of Europe.%记述了原长翅亚目化石(Protomecoptera Tillyard,1917)在中国陕西铜川中三叠统中的首次发现,填补这个亚目化石在中国的空白.根据脉序特征,确定是2个新属、种:Glytochorista martynovae gen.et sp.,Phyllochorista orientis gen.et sp.nov.,属这个亚目的汤姆蝎蛉科Tomichoristidae O.Martynova,1958,从而将这个科的化石推向最高层位,即从早二叠世推向中三叠世,跨时5000多万年.从这个意义来讲,对研究该科从古生代晚期向中生代早期的演化有一定的重要参考价值.化石采自铜川中三叠世铜川组下段上部灰绿色泥页岩.新属、新种属于陕西昆虫群(系中三叠世陕西动物群或陕西生物群的一个化石门类)铜川昆虫组合的新成员,时代相当于欧洲拉丁尼期(Ladinian stage).
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