Cascoplecia insolitis (Diptera: Cascopleciidae), a new family, genus, and species of flower-visiting, unicorn fly (Bibionomorpha) in Early Cretaceous Burmese amber

Cascoplecia insolitis (Cascopleciidae), a new family, genus, and species of Bibionomorpha are described from Early Cretaceous Burmese amber. The new family is characterized by the following combination of characters: small size (wing length, 3.2 mm); head reduced, deflexed; antennomeres 2–12 sinuate; three ocelli raised on an extended horn-like protuberance; mouthparts reduced except for well developed maxillary palps with elongate terminal palpomere; femora long; all tibiae with apical spines; pulvilli and empodia pad-like, setose; Sc terminates at half wing length; r-m crossvein located before middle of wing; R 2 + 3 longer than Rs; R 4 + 5 more than twice the length of Rs; bRs longer than dRs. The fossil presents an interesting combination of strongly canalized (conserved) and de-canalized (specialized) characters. Pollen grains associated with the tarsi show that Cascoplecia was a flower-visitor that probably pollinated angiosperms in the Burmese amber forest.