A peculiar species of mole cricket (Orthoptera: Gryllotalpidae) from mid-Cretaceous Kachin amber of northern Myanmar

A patchy fossil record and limited information is available for understanding the early evolution of Gryllotalpidae, which is a specialized orthopteran family with fossorial habits. Herein, a new mole cricket species, Tresdigitus gracilis sp. nov., is described and attributed to the genus Tresdigitus mainly based on its quadrate pronotum equal to the head in width, protibia with three setose movable dactyls, mesotibia with four apical spurs, and metatibia with denticle-like spines distributed on the distal 2/3rds of its length and six spurs apically. It is mainly distinguished from Tresdigitus rectanguli Xu et al., 2020 in the head not being hidden under the pronotum, head with a distinct 'Y-shaped' ecdysial suture, the pronotum is nearly equal to the head in length, and the metatibia with fifteen denticle-like spines interspersed on upper margin. Mouthpart of the new species is well-preserved, and its blunt lacinia probably indicates that Tresdigitus gracilis sp. nov. was graminivorous. Additionally, keys to genera and species of fossil gryllotalpids in Cretaceous Kachin (northern Myanmar) and France amber is provided.(c) 2022 Elsevier Ltd. All rights reserved.