Cylindrical bark beetles (subfamily Colydiinae) are a group of mycophagous and predatory beetles placed in the family Zopheridae with a complicated taxonomic history and an unresolved phylogeny. We describe a new genus and two new species of strikingly cylindrical and elongate colydiid beetles from mid-Cretaceous Burmese amber mined in northern Myanmar (ca99 Ma).Bifurderum minutumgen. et sp. nov. andB. donoghueigen. et sp. nov. show a puzzling combination of characters including antennal and mandibular insertions concealed dorsally, 11-segmented antennae with a loose 2-segmented club, apical antennal segment not enclosed in the preceding antennomere, open procoxal cavities, prosternal process as wide as the maximum diameter of the procoxae and not expanding apically to close the procoxal cavities, narrowly separated metacoxae, and tarsi simple. The unusual body form ofBifurderumgen. nov. points towards a predatory life inside the galleries of wood-boring insects. The new fossils substantially expand the known range of morphological disparity in Mesozoic colydiid beetles and suggest that adaptation for life in the galleries of xylophagous insects in cylindrical bark beetles evolved by the mid-Cretaceous.