Expanding the Mesozoic Record of Early Brachyceran Fly Larvae, including New Larval Forms with Chimera-Type Morphologies.

Diptera are one of the four megadiverse groups of holometabolan insects. Flies perform numerous ecological functions, especially in their larval stages. We can assume that this was already the case in the past; however, fly larvae remain rare in most deposits. Here we report new dipteran larvae preserved in Cretaceous (about 99 Ma) Kachin amber from Myanmar and, even older, Jurassic (about 165 Ma) compression fossils from China. Through light microscopy and micro-CT scanning we explore their peculiar morphology and discuss their possible phylogenetic affinities. Several larvae seem to represent the lineage of Stratiomyomorpha. A few others present characters unique to Xylophagidae (awl-flies), as well as to Athericidae (water sniper-flies), resulting in a chimeric morphology. Understanding the exact relationships of most of these specimens with a particular lineage remains challenging, since they differ considerably from any other known dipteran larvae and present some unique traits. Additionally, we report new specimens of Qiyia jurassica Chen et al., 2014, supposedly parasitic larvae, most likely representatives of Athericidae. These new findings offer valuable insights into the evolution of the early diversification of the brachyceran flies and underscore the importance of immature stages in understanding the evolutionary history and ecology of flies.

Four new species and some new records of Brazilian frog-biting midges (Diptera: Corethrellidae).

Four new species of Corethrella are described from Brazil. Corethrella xokleng sp. n. and C. cambirela sp. n. are described from males and females, and Corethrella yanomami sp. n. and C. munteantaroku sp. n. are described from a female and male, respectively. Fourteen Corethrella species have new distributional records, with five of these being first records for Brazil. The number of valid species of Corethrellidae known from Brazil is increased from 37 to 46.

New species and records of frog-biting midges from southern Brazil (Diptera: Corethrellidae).

Corethrella borkenti sp. n. is described, based on female and male adults, pupae and larvae, collected from tank bromeliads in the Atlantic Forest of southern Brazil. The larva and pupa of C. alticola Lane, 1939 are described for the first time. New distributional records for C. alticola and C. vittata Lane, 1939 extend their distributions to the southern Atlantic Forest. A key to pupae of peruviana group is given.