Bibionidae, also called March flies, is a widespread group of Nematocera and their fossils are very abundant in lacustrine deposits especially in the Oligocene and Miocene, but records as amber inclusions in the Mesozoic are quite rare. Here, we describe a new genus and species of March fly, Protopenthetria skartveiti gen. et sp. nov. from mid-Cretaceous Burmese amber. The new genus and species described and illustrated based on a well-preserved male specimen. A key to all known genera and species of Bibonidae from Burmese amber is given. The discovery of Protopenthetria skartveiti gen. nov. et sp. nov. provides evidence about the morphology of Bibionidae in the Mesozoic and illustrates the high diversity of the Burmese amber biota. (c) 2021 Elsevier Ltd. All rights reserved.