Simple Summary
As a relict family within Neuroptera, Ithonidae sensu lato exhibit a relatively rich fossil record. However, severely underrepresented Cretaceous diversity (especially during the Late Cretaceous) and the lack of fossil calibration for key traits impede the comprehensive understanding of Ithonidae’s evolutionary history. This study describes one new genus and species from the mid-Cretaceous Kachin amber, Cretithone zhangi gen. et sp. nov., and assigns it to the Principiala genus-group. Cretithone gen. nov. shows a closer systematic position to Phyllithone Liu, Lu, Wang, Xu and Zhuo, 2025, as evidenced by shared forewing characteristics.
Abstract
One new genus and species of Ithonidae, Cretithone zhangi gen. et sp. nov., is described from the mid-Cretaceous Kachin amber. Cretithone gen. nov. is distinguished from other fossil ithonids by the combination of the following characteristics: exceptionally broad costal space; proximal branches of RP fused into a single vein and then fused with M; medial branches of RP fused with each other; simple basal M, with marginal forks; CuA divided into two main branches, the anterior branch with posteriorly directed subbranches and the posterior branch with anteriorly directed subbranches; and most proximal branches of CuP fused with adjacent branches. The new genus and species has been assigned to the Principiala genus-group by the fusion of the proximal branches of RP and the peculiar configuration of M and CuA. Variations in the forewing characteristics among the fossil ithonids are briefly discussed.