Complex sentence: Riek (1976) originally considered Palaeontinoidea to be the descendants of the family Cicadoprosbolidae (currently known as the family Tettigarctidae), insects believed to be transitional between the ancestral cicada-like family Prosbolidae and the modern family Cicadidae.
Split into simpler sentences: Riek (1976) originally considered Palaeontinoidea to be the descendants of the family Cicadoprosbolidae. The family is a synonym of family Tettigarctidae, insects believed to be transitional between the ancestral cicada-like family Prosbolidae and the modern family Cicadidae.