The first fossil false click beetle larva preserved in amber

Abstract

AbstractWe report a new and unusual beetle larva preserved in ca. 100 million-year-old Kachin amber. Larvae of many modern lineages of beetles are associated with wood, breaking it into smaller pieces or directly digesting it. With such a lifestyle, beetle larvae are important for carbon cycling. We can assume that this is not only the case in modern ecosystems, but was similar in the past. Yet, wood-associated beetle larvae seem so far rare in Kachin amber despite its otherwise rich record of many different ecotypes. Only recently, solid-wood-boring larvae and those living in decaying wood have been reported from this amber deposit. Larvae of the group Eucnemidae, false click beetles, which are also wood-associated, have so far been only known from sedimentary rock deposits. Here we report the first larva of a false click beetle preserved in amber. The fossil larva combines features of different modern lineages of Eucnemidae in a unique morphology that is not known in the modern fauna. The fossil adds to the growing number of wood-associated holometabolan larvae in Kachin amber and with this contributes to a more complete view on this now extinct community and ecosystem.