|Publication Type:||Conference Paper|
|Year of Publication:||2016|
|Authors:||L. Li, Shih, C., Ren, D.|
|Conference Name:||The 7th International Conference on Fossil Insects, Arthropods and Amber|
|Publisher:||Siri Scientific Press|
|Conference Location:||National Museum of Scotland, Edinburgh|
The Lower Cretaceous Yixian Formation and the Middle Jurassic Jiulongshan Formation, both located in northeastern China, have yielded many well preserved apocritan fossils. Based on morphologic characters of these apocritans, we have conducted taxonomic studies and, in some cases, phylogenetic analyses to provide insights of their evolutionary trends, origination and dispersal, and potential roles in the palaeoecosystems. Up to date, we have described 49 new species in 17 new genera and eight families: Anomopterellidae, Ephialtitidae, Evaniidae, Heloridae, Mesoserphidae, Pelecinidae, Praeaulacidae and Scolebythidae. Three cases of key findings will be presented:• Based on the research of the broad articulation between the propodeum and metasoma in basal Ephialtitidae, we suggested three separate pathways of the transformation of the “wasp waist” in three different derived lineages leading from Ephialtitidae to: (i) Kuafuidae and further to the remaining Apocrita, (ii) Stephanidae, and (iii) Evanioidea. • According to phylogenetic analyses and the temporal and spatial distribution of pelecinids, the most parsimonious hypothesis is that the basal species initially originated in northeastern China and spread to central and eastern Asia, and then dispersed to the Americas. • In Evaniidae, except for three genera from the Cenozoic, all thirteen other genera are from the Cretaceous, suggesting that Evaniidae most likely originated in the Late Jurassic or near the Jurassic–Cretaceous boundary, and radiated in the Early Cretaceous. These findings from the Middle Jurassic to the Early Cretaceous of northeastern China have enhanced our knowledge of Apocrita and provided a foundation for future studies with new fossil (including amber) specimens.