A Mesozoic clown beetle myrmecophile (Coleoptera: Histeridae)

Abstract

Complex interspecies relationships are widespread among metazoans, but the evolutionary history of these lifestyles is poorly understood. We describe a fossil beetle in 99-million-year-old Burmese amber that we infer to have been a social impostor of the earliest-known ant colonies. Promyrmister kistneri gen. et sp. nov. belongs to the haeteriine clown beetles (Coleoptera: Histeridae), a major clade of ‘myrmecophiles’—specialized nest intruders with dramatic anatomical, chemical and behavioral adaptations for colony infiltration. Promyrmister reveals that myrmecophiles evolved close to the emergence of ant eusociality, in colonies of stem-group ants that predominate Burmese amber, or with cryptic crown-group ants that remain largely unknown at this time. The clown beetle-ant relationship has been maintained ever since by the beetles host-switching to numerous modern ant genera, ultimately diversifying into one of the largest radiations of symbiotic animals. We infer that obligate behavioral symbioses can evolve relatively rapidly, and be sustained over deep time.

Phylogeny and evolution of Mesozoic and extant lineages of Histeridae (Coleoptera), with discovery of a new subfamily Antigracilinae from the Lower Cretaceous

“…Given the biological evidence from previous research (Kistner, 1982; Parker, 2016; von Beeren and Tishechkin, 2017), the groups inhabiting ant and termite nests are mostly clustered within “Histeromorphae” in the present trees (Figs 1–3). The present results, as well as a recent study on Promyrmister (Haeteriine) from Burmese amber (Zhou et al, 2019a) which exhibits anatomical, chemical and behavioural adaptations for colony infiltration, suggest that host switching may explain the great longevity of the clown beetle‐ant symbiosis to the present. We suggest that this symbiotic‐living habitus may have provided a unique adaptive zone, leading to much of the current biodiversity of “Histeromorphae”, especially in association with modern Formicidae, which have diversified since the Eocene (Barden, 2017).…”

Diversification of myrmecophilous Clavigeritae beetles (Coleoptera: Staphylinidae: Pselaphinae) and their radiation in New Caledonia

“…What is presumably the case, however, is that the species richness of recent Clavigeritae – one of the most speciose clades of myrmecophiles – has likely been contingent on their capacity to utilize diverse ants as hosts. Host switching opens up potential niche space and provides opportunities for speciation; it can also help to circumvent coextinction with hosts (Zhou et al ., 2019). Host switching appears to be characteristic of the most species‐rich groups of obligate myrmecophiles, including Paussinae (Moore & Robertson, 2014) and Hetaeriinae (Histeridae) (Zhou et al ., 2019).…”

“…Host switching opens up potential niche space and provides opportunities for speciation; it can also help to circumvent coextinction with hosts (Zhou et al ., 2019). Host switching appears to be characteristic of the most species‐rich groups of obligate myrmecophiles, including Paussinae (Moore & Robertson, 2014) and Hetaeriinae (Histeridae) (Zhou et al ., 2019). In contrast, highly‐host specific clades that show negligible host switching, such as the many convergent lineages of Aleocharinae (Staphylinidae) that utilize specific army ant species as hosts (Maruyama & Parker, 2017), are closely tied to the evolutionary fate of a single host.…”

Molecular evolution of gland cell types and chemical interactions in animals

“…Dozens of socially parasitic clades of rove beetles (Staphylinidae) and clown beetles (Histeridae) have evolved unique thoracic and abdominal glands, producing uncharacterized 'appeasement' compounds for host behavioral manipulation (Fig. 1E,F) (Kistner, 1979;Parker, 2016;Parker and Grimaldi, 2014;Pasteels, 1969;Zhou et al, 2019). Exocrine signals play equivalently critical and diverse roles in vertebrate social behaviors ( Fig.…”