A new genus and species of Elcanidae (Insecta: Orthoptera) from Cretaceous Burmese amber

The Oldest Representatives of Tree Crickets (Orthoptera: Gryllidae; Oecanthinae) from Northern Myanmar

Simple Summary

Two new genera and two new species of Oecanthinae (Gryllidae) are described that are from northern Myanmar amber. They are the oldest representatives of tree crickets, supporting the previous estimation of the origin of Oecanthinae by molecular data. These new findings improve our knowledge of the evolution of the Gryllidae.

Abstract

The abundance of insects in Burmese amber illustrates a highly diverse insect community of the mid-Cretaceous, but the records of crickets are relatively rare. Here, we erect two new genera with two new species, Birmanioecanthus haplostichus gen. et sp. nov. and Apiculatus cretaceus gen. et sp. nov., based on two new specimens from northern Myanmar amber. These new species can be assigned to the subfamily Oecanthinae (Orthoptera: Gryllidae) by their prognathous head, slender body and metatibiae, and protibiae with large tympana. These new findings are the first and earliest fossil record of tree crickets and shed light on the evolution of Oecanithinae.

Aposematic coloration from Mid-Cretaceous Kachin amber

Aposematic coloration is among the most diverse antipredator strategies, which can signal unpleasantness of organisms to potential predators and reduce the probability of predation. Unlike mimesis, aposematic coloration allows organisms to warn their predators away by conspicuous and recognizable colour patterns. However, aposematism has been a regular puzzle, especially as the long-term history of such traits is obscured by an insufficient fossil record. Here, we report the discovery of aposematic coloration in an orthopteran nymph from Mid-Cretaceous Kachin amber (99 million years old). It is attributed to the extinct family Elcanidae and erected as a new genus identified by conspicuous dark/light-striped coloration, four apical spurs on the metatibia, a two-segmented metatarsus and unsegmented stylus. It represents the first fossil orthopteran preserved with aposematic coloration from the Mesozoic, demonstrating that orthopterans had evolved aposematism by the Mid-Cretaceous. Our findings provide novel insights into the early evolution of anti-predator strategies among orthopterans. Together with mimesis, debris-carrying camouflage and aposematism previously reported, our findings demonstrate the relative complexity of prey-predator interactions in the Mesozoic, especially in the Mid-Cretaceous Kachin amber forest. This article is part of the theme issue 'The impact of Chinese palaeontology on evolutionary research'.

A world key to the genera of Elcanidae (Insecta, Orthoptera), with a Jurassic new genus and species of Archelcaninae from China

A new fossil genus and species is described from the Middle Jurassic of China. The type of Sinoelcana minuta gen. et sp. nov. has body and legs preserved. It is distinguished from all other elcanids by the unique combination of wing venation and stout ovipositor. The sickle-shaped ovipositor suggests that the new species had a preference for oviposition on plant material. A world key to the genera of Elcanidae is provided based on the wing venation.

The first Elcanidae (Orthoptera, Elcanoidea) from the Daohugou fossil bed of northeastern China

A new species of Elcanidae (Orthoptera, Elcanoidea), Parelcana pulchmacula sp. nov., is described based on four new specimens from the Middle Jurassic Jiulongshan Formation of northeastern China. The new species differs from all other known Archelcaninae species by its combination of wing-venation characters. This new finding improves our knowledge of variation on wing venation in elcanid insects and constitutes the first record of Elcanidae from the Daohugou fossil bed (Yanliao Biota) of northeastern China.