Search Results (3)

Herein, we present a systematic investigation of plant fossils from the Yingzuilazi Formation in Baishan City, Jilin Province, China. The Baishan flora comprises 27 genera and 46 species. They are predominantly autochthonous or parautochthonous, based on their floral composition and taphonomic attributes. An analysis of paleoecological characteristics of the fossil plant assemblages, combined with the habitat preferences of analogous modern communities, allowed us to reconstruct the Early Cretaceous plant communities in the Baishan Basin: a riparian–wetland community, lowland community, montane slope community, and montane highland community. The floral composition, a statistical analysis of foliar physiognomy, and the palynofloral characteristics indicated a warm and humid temperate climate during the deposition of the Yingzuilazi Formation. A genus-level comparison with the Yixian Formation flora of western Liaoning revealed high compositional similarity, which confirms the Baishan flora as the easternmost distribution of the Jehol Biota in China. This study provides new fossil evidence for understanding Early Cretaceous floristic provincialism and paleoenvironmental reconstruction in East Asia. It offers geological references that can predict vegetation responses to a greenhouse climate. Additionally, Sphenopsida and Filicopsida may serve as potential indicators that may identify favorable terrestrial shale oil and gas reservoirs from the Early Cretaceous. Full article

Rheanischia new genus, type species Rheanischia brevicornis new species (Eucnemidae, Anischiinae) is described from the Lower Cretaceous of Liaoning, China. The presence of this species in early Cretaceous deposits provides new insight into the evolution of basal lignicolous Eucnemidae clades. Both Anischiinae and Palaeoxeninae species diversified in a world dominated by gymnosperms, before the main radiation of angiosperms. More than 95% of modern eucnemid larvae have a Palaeoxenus-type highly modified head structure, but contrary to the Palaeoxenus larva, they develop in angiosperm wood. Anischiinae utilize angiosperms as well, but their head capsule shows no such modifications. These facts prove that highly specialized morphological features do not offer definite proof of similar way of life in the distant past, nor should non-modified structures be taken as proof for another kind of substrate choice. Eucnemidae have invaded angiosperms with two quite different morphological adaptations. This fact may have implications for the evolution of all clicking elateroids. Full article

The Confuciusornithiformes represent the most stem-ward avian occurrence of an edentulous rostrum. Although a keratinous beak is widely considered to have covered the rostrum in confuciusornithiforms, this feature is almost never preserved, having been previously reported only in the holotype of Confuciusornis dui and the holotype of Eoconfuciusornis zhengi. This strongly contrasts with the widespread preservation of the keratinous sheaths that cover the manual and pedal ungual phalanges. Here, we report on a third occurrence of a preserved rhamphotheca in a specimen of Confuciusornis sanctus. We illuminated the preserved traces using laser-stimulated fluorescence. Similarly to E. zhengi, the rhamphotheca has been preserved only as a two-dimensional trace, whereas ungual sheaths are preserved in three dimensions. In contrast to the traces preserved in C. dui, the rhamphotheca in the discussed specimen of C. sanctus is straight rather than upturned. This hints towards hidden morphological diversity within the thousands of Confuciusornis specimens, in which species may be further differentiated by soft tissue features or behaviors, much like many living birds, that cannot be detected in fossils, even with exceptional preservation. Full article