|Publication Type:||Conference Paper|
|Year of Publication:||2016|
|Authors:||C. Shih, Gao, T., Labandeira, C. C., Li, L.|
|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 and Middle Jurassic Jiulongshan Formations of northeast China have yielded well preserved fossil plants, insects and vertebrates which have provided a significant amount of palaeoecological data for demonstrating the ubiquity of autecologic relationships. We present nine categories of biotic associations involving seven orders of insects that interacted with coexisting plants, other insects and vertebrates.There are four examples of associations with plants: (1) The pollination mutualism was demonstrated by three families of pollinating Mecoptera that evolved convergent long-proboscid siphonate mouthparts for consumption of pollination drops from tubules or channels in gymnosperm ovulate organs; (2) Mimesis or camouflage was present in two lacewing taxa (Neuroptera) that imitated co-occurring pinnate gymnosperm pinnules; (3) Similarly, a scorpionfly (Mecoptera) involved mimicry of an entire, co-occurring ginkgo leaf, presumably providing mutual protection to the plant model and the insect mimic; (4) Considerable insect damage occurred on a variety of plants involving galls by beetles (Coleoptera) and stylate punctures and margin feeding, probably by Hemiptera and Orthoptera, respectively, among others, on vascular-plant tissues. There are three instances of associations with other insects: (1) Parasitoidy was implied by ovipositors of apocritan wasps such as Ephialtitidae and Pelecinidae (Hymenoptera); (2) Male‒male competition and sexual display were represented by two genera of Mecoptera with exaggerated male organs; (3) Reproduction was highlighted by a pair of copulating froghoppers (Hemiptera), hitherto the earliest record of copulating insects in flagrante delicto. Last, we report two cases of associations with vertebrates: (1) Integumental blood feeding was established by ectoparasites, such as early and transitional fleas (Siphonaptera) that possessed long beaks consisting of robust, outwardly directed, serrated stylets involved in piercing thick vertebrate integument and imbibing host blood and possibly lymph; (2) Two taxa of the earliest known blood-feeding true bugs (Hemiptera) were discovered from the use of geochemical methods for determining their diets and a combination of morphological and taphonomic data. These intricate associations provide an expanded understanding of the ecologic role and evolutionary developments that insects had with other organisms in mid-Mesozoic ecosystems.