Flower-Associated Brachycera Flies as Fossil Evidence for Jurassic Angiosperm Origins

Abstract

Pollinating insects played a decisive role in the origin and early evolution of the angiosperms. Pollinating orthorrhaphous Brachycera fossils (short-horned flies) collected from Late Jurassic rocks in Liaoning Province of northeast China provide evidence for a pre-Cretaceous origin of angiosperms. Functional morphology and comparison with modern confamilial taxa show that the orthorrhaphous Brachycera were some of the most ancient pollinators. These data thus imply that angiosperms originated during the Late Jurassic and were represented by at least two floral types.

Biogeographic analysis of Crocidiinae (Diptera, Bombyliidae): finding congruence among morphological, molecular, fossil and paleogeographical data

“…Furthermore, its hypothesized sister-group, Mythicomyiidae, is recorded from the Middle Jurassic (163-185 Mya), also from Russia (Evenhuis 2002). The Late Jurassic fossil (Ren 1998) is in agreement with the age estimated by molecular studies (discussed above), although the sister-group of Bombyliidae indicates a more ancient age, in the Middle Jurassic. Even so, it is not incongruent with the molecular-based age, as the latter estimated an origin for Bombyliidae ranging from 140 to 190 Mya.…”

“…The oldest described bombyliid fossils are from Eocene (Fig. 3), but Ren (1998) reported an undetermined putative bombyliid fossil from the Siberian Late Jurassic rocks. This information needs to be confirmed, as the specimen was not examined by any Bombyliidae taxonomist.…”

“…If Crocidiinae diversification is based on vicariance, then the origin of the clade could be dated close to this time. Corroborating this date, there exist a molecular analysis dating the origin of Bombyliidae to 140-190 Mya (Wiegmann et al 2003), while an undetermined fossil of Bombyliidae is recorded from Late Jurassic (Ren 1998) and a Mythicomyiidae fossil from Middle Jurassic (Evenhuis 2002). Therefore, the most basal event separated the ancestral crocidiine lineage into a Nearctic clade originating Desmatomyia and Inyo from another clade originating the remaining genera.…”

The Pollination of Mid Mesozoic Seed Plants and the Early History of Long-proboscid Insects1,2,3

“…2, 9) are first known from Middle Jurassic Eurasian deposits that reveal siphonate proboscises either for nectaring, as in the case of the Nemestrinidae, or conceivably involved in bifunctional siphonate-stylate proboscises that would involve nectaring in males and joint nectaring and blood feeding in conspecific females, as in the pangioniine horseflies of the Tabanidae (Mostovski, 1998;Ren, 1998a;Mazzarolo & Amorim, 2000;Labandeira, 2005a). However, these mid Mesozoic clades are implicated in feeding only on surface fluids based on distinctive siphonate proboscises and associated mouthpart features (Mostovski, 1998;Ren, 1998b;Labandeira, 2005a), clumps of gymnospermous Classopollis pollen on their heads (Labandeira, 2005a; also see Nicholson, 1994), and high pollination-drop nutritive values from extant insectpollinated gymnosperms (Labandeira et al, 2007a;Nepi et al, 2009). Accordingly, these nectarivorous and palynophagous brachyceran flies initially targeted gymnospermous seed plants during the Middle Jurassic and evidently transferred their diets to angiosperms during their initial radiation of the Early Cretaceous.…”

“…The long-proboscid siphonate condition in mid Mesozoic Diptera: families Nemestrinidae and Cratomyiidae. -A. Overlay drawing of dorsal aspect of head, proboscis, and pro thoracic legs of Protonemestrius jurassicus Ren (Ren, 1998a) (Nemestrinidae), from the mid Early Cretaceous of northeastern China, enlarged from B at right; CNU-LB1997-005; scale bar = 1 mm. The comparatively thin and gracile proboscis length is ca.…”