Origin and evolution of fungus farming in wood‐boring Coleoptera – a palaeontological perspective

Abstract

Insect-fungus mutualism is one of the better-studied symbiotic interactions in nature. Ambrosia fungi are an ecological assemblage of unrelated fungi that are cultivated by ambrosia beetles in their galleries as obligate food for larvae. Despite recently increased research interest, it remains unclear which ecological factors facilitated the origin of fungus farming, and how it transformed into a symbiotic relationship with obligate dependency. It is clear from phylogenetic analyses that this symbiosis evolved independently many times in several beetle and fungus lineages. However, there is a mismatch between palaeontological and phylogenetic data. Herein we review, for the first time, the ambrosia system from a palaeontological perspective. Although largely ignored, families such as Lymexylidae and Bostrichidae should be included in the list of ambrosia beetles because some of their species cultivate ambrosia fungi. The estimated origin for some groups of ambrosia fungi during the Cretaceous concurs with a known high diversity of Lymexylidae and Bostrichidae at that time. Although potentially older, the greatest radiation of various ambrosia beetle lineages occurred in the weevil subfamilies Scolytinae and Platypodinae during the Eocene. In this review we explore the evolutionary relationship between ambrosia beetles, fungi and their host trees, which is likely to have persisted for longer than previously supposed.

Lessons From Insect Fungiculture: From Microbial Ecology to Plastics Degradation

“…Fungus farming in Curculionidae weevils evolved independently at least 13 times in the subfamily Scolytinae and one time in the subfamily Platypodinae ( Jordal and Cognato, 2012 ; Biedermann and Vega, 2020 ). This polyphyletic assemblage of ecologically similar weevils includes ambrosia beetles, derived from phloeomycetophagous bark beetles ( Jordal and Kambestad, 2014 ; Kasson et al, 2016 ; Biedermann and Vega, 2020 ; Peris et al, 2021 ). Bark beetles (Coleoptera: Curculionidae: Scolytinae) are woodborer weevils that breed in the phloem (i.e., inner bark) of woody plants.…”

First fossil species of ship-timber beetles (Coleoptera, Lymexylidae) from Eocene Rovno amber (Ukraine)

“…All known members of the family develop in wood as larvae and mutualism with fungi has been reported for a few species (Batra and Francke-Grosmann 1961;Wheeler 1986;Young 2002;Lawrence 2010;Casari and Albertoni 2013;Toki 2021), although more rigorous study and evidence are needed if the other unstudied lymexylid beetles are strongly connected with fungi (Lawrence 2010). Recently, Peris et al (2021) discussed a potentially crucial role of the lymexylids as wood-boring insects, with a special emphasis on the insect-fungus mutualism, more specifically the cultivate ambrosia fungi and their associations. Moreover, Peris et al (2021) considered that Lymexylidae might actually be one of the ambrosia beetles based on the fact that some of their larvae feed primarily on symbiotic ambrosia fungi in tunnels or caves in woody tissues following the criteria by Kirkendall et al (2015).…”

“…Recently, Peris et al (2021) discussed a potentially crucial role of the lymexylids as wood-boring insects, with a special emphasis on the insect-fungus mutualism, more specifically the cultivate ambrosia fungi and their associations. Moreover, Peris et al (2021) considered that Lymexylidae might actually be one of the ambrosia beetles based on the fact that some of their larvae feed primarily on symbiotic ambrosia fungi in tunnels or caves in woody tissues following the criteria by Kirkendall et al (2015).…”

“…Five species in four genera of the subfamily Atractocerinae have recently been described from mid-Cretaceous Burmese (Kachin) amber (Chen 2019;Yamamoto 2019;Chen and Zhang 2020), with some unstudied material (e.g. Peris 2020Peris , 2021Yamamoto, pers. obs.).…”

35 million-year-old solid-wood-borer beetle larvae support the idea of stressed Eocene amber forests

“…It has been suggested that the extensive production of resin at least in some amber forests was a result of stress (McKellar et al 2011;Seyfullah et al 2018). More precisely, water stress of the resin-producing trees might have been the cause (Martínez-Delclòs et al 2004;Labandeira 2014;Seyfullah et al 2018), possibly mediated by drought, flood diseases, wildfires, or plant parasites (though the impact of plant parasites has been questioned: Peris et al 2016;Peris and Rust 2020; but see also Peris 2020 andPeris et al 2021). Baranov et al (2021) recently reported a large number of hoverfly larvae (Syrphidae) of the group Volucellini preserved in Baltic amber.…”