Enormously long, siphonate mouthparts of a new, oldest known spongillafly (Neuroptera, Sisyridae) from Burmese amber imply nectarivory or hematophagy

Paradoxosisyra groehni gen. et sp. nov. (Neuroptera: Sisyridae) is described from Upper Cretaceous (lowest Cenomanian) Burmese amber as the oldest known sisyrid. The new genus is assigned to the new subfamily Paradoxosisyrinae, which is characterized by enormously long siphonate mouthparts, very long and slender hind legs, several setiferous calluses on the head and pronotum; deeply forked CuP and AA1 veins in the forewing; a complete inner gradate series of crossveins, and the RP vein with five branches in the hind wing. The greatly lengthened, laterally flattened galea and lacinia, and the labial ligula transformed into a long acute stylet are characteristic of only this species and do not occur in other insects. These siphonate mouthparts were likely used primarily to feed on flower nectar. The possibility remains, however, that the species was hematophagous (possibly facultative), feeding on the hemolymph of arthropods or the blood of such thin-skinned vertebrates as frogs.