A new pterosaur (Pterosauria) from Middle Jurassic Tiaojishan Formation of western Liaoning,China

A new pterosaur Archaeoistiodactylus linglongtaensis gen. et sp. nov. is erected based on an incomplete skeleton with a partial skull and lower jaw. The new taxon is characterized by circular tooth sockets of anterior mandibular teeth,the anterior teeth of the upper jaw bearing posteriorly directed crowns,a relatively short metacarpus,and wing phalanges 2 and 3 and the tibia subequal in length. It possesses some plesiomorphic characters such as short metacarpals and circular tooth sockets. The pointed jaw tip present in the new taxon indicates that the expanded jaw tips of later istiodactylids are a derived character state,and the new taxon represents the first istiodactylus-like pterosaur found from the pre-Late Jurassic deposits,which provides a key role in our understanding the origin and evolution of the known istiodactylid pterosaurs. Archaeoistiodactylus is regarded as the ancestor form of the known istiodactylid pterosaur.

内心的一座园子

乡村的盛夏,有着最为饱满的繁华。花开得灿烂,瓜果丰美。对于我们这群生活在钢筋水泥丛林中的00后来说,别提有多向往了。暑假回乡看外婆时,我总要嚷着住上几晚,为的就是能和菜园多几次'亲密接触'。清晨,小脚丫踩在凉丝丝的土地上,小草把我的脚踝刺得痒痒的,菜园一大片绿汪汪的菜畦,好像在聆听篱笆上缠绕的牵牛花播放歌曲。