| Summary: | One new genus and species, <i>Leptoxyela eximia</i> gen. et sp. nov., and one new species, <i>Scleroxyela cephalota</i> sp. nov., are described and illustrated based on two well-preserved compression fossils from the Lower Cretaceous Yixian Formation and the Middle Jurassic Jiulongshan Formation of China, respectively. <i>Leptoxyela eximia</i> gen. et sp. nov. is placed in the tribe Angaridyelini, 1966 and <i>Scleroxyela cephalota</i> sp. nov. in the tribe Xyeleciini Benson, 1945; while both tribes are in the subfamily Macroxyelinae Ashmead, 1898 of Xyelidae. A key to the genera of Angaridyelini is provided. In addition, we investigated various angles between Rs+M and 1-Rs for known fossil species of Macroxyelinae, and we found the angle and the length of 1-Rs are correlated; however, we could not see any correlation between the angles and the fossil ages even within a tribe. Furthermore, based on Sc<sub>2</sub> connected to R before Rs, the angle between Rs+M and 1-Rs, and the length of the first flagellomere, we believe that the tribe Ceroxyelini may have only one genus of <i>Ceroxyela</i>, and suggest that <i>Isoxyela</i> and <i>Sinoxyela</i> should be transferred to Gigantoxyelini.
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