Elcanidae (Insecta, Orthoptera) from the Crato Formation, Araripe Basin: Exquisite preservation and ecological implications

Elcanidae is one of the most abundant orthopteran families in the Crato Formation (Aptian), northeastern Brazil. However, its high-fidelity preservation and ecological importance within the context of the Crato fauna have not yet been studied. Here, we present a taphonomic and morphological analysis of elcanids from this Konservat-Lagerstätte and their relationship with the depositional lacustrine environment. We propose that the Crato elcanids inhabited areas near lake’s borders, including oviposition close to its margins, which facilitated their preservation. In addition, their abundance may be the result of sudden climatic events that led to aerial deposition into the aquatic environment. Finally, we propose that the metatibial leaf-like spurs may have played a role in camouflage, while the dark coloration on the tegmina could have served a defensive function. Our findings further contribute to the taxonomic and morphological diversity of this extinct taxon from the Crato Formation. • Cretaceous Araripe Basin elcanids exhibit three-dimensional preservation • Crato Formation elcanids camouflage themselves in their environment through leaf mimicry. • The abundance of elcanids in the Crato Formation yellowish limestone may result from warm climatic events. • Elcanids' ecological niche was related to a paleolake, including oviposition along its margins.