The first described turtle beetles from Eocene Baltic amber, with notes on fossil Chelonariidae (Coleoptera: Byrrhoidea)

Abstract

Chelonariidae, or turtle beetles, are rarely represented in the fossil record. Two new extinct species of this thermophilous coleopteran family, Chelonarium andabata Alekseev and Bukejs sp. nov. and Ch. dingansich Alekseev and Bukejs sp. nov., are described and illustrated from Eocene Baltic amber using X-ray micro-computed tomography (micro-CT). They are the first formally described species of turtle beetles from Eocene Baltic amber and the first known European representatives of this family. Based on modern habitats of the group, the presence of the plants with which their larvae are associated (epiphytic orchids) is proposed in the Eocene amber forest. The Eocene Florissant Formation fossil Chelonarium montanum Wickham, 1914, which was originally placed within Chelonariidae, is discussed based on its original description, and placement as incertae sedis within Byrrhoidea is proposed for this compression fossil (http://zoobank.org/References/C2EE164D-59DD-42FE-937D-B01C78DCD228, last access: 8 February 2021).