The beetle tree of life reveals thatColeoptera survived end‐Permian mass extinction to diversify during theCretaceous terrestrial revolution

Abstract

Abstract.Here we present a phylogeny of beetles (Insecta: Coleoptera) based on DNA sequence data from eight nuclear genes, including six single-copy nuclear protein-coding genes, for 367 species representing 172 of 183 extant families. Our results refine existing knowledge of relationships among major groups of beetles. Strepsiptera was confirmed as sister to Coleoptera and each of the suborders of Coleoptera was recovered as monophyletic. Interrelationships among the suborders, namely Polyphaga (Adephaga (Archostemata, Myxophaga)), in our study differ from previous studies. Adephaga comprised two clades corresponding to Hydradephaga and Geadephaga. The series and superfamilies of Polyphaga were mostly monophyletic. The traditional Cucujoidea were recovered in three distantly related clades. Lymexyloidea was recovered within Tenebrionoidea. Several of the series and superfamilies of Polyphaga received moderate to maximal clade support in most analyses, for example Buprestoidea, Chrysomeloidea, Coccinelloidea, Cucujiformia, Curculionoidea, Dascilloidea, Elateroidea, Histeroidea and Hydrophiloidea. However, many of the relationships within Polyphaga lacked compatible resolution under maximum-likelihood and Bayesian inference, and/or lacked consistently strong nodal support. Overall, we recovered slightly younger estimated divergence times than previous studies for most groups of beetles. The ordinal split between Coleoptera and Strepsiptera was estimated to have occurred in the Early Permian. Crown Coleoptera appeared in the Late Permian, and only one or two lineages survived the end-Permian mass extinction, with stem group representatives of all four suborders appearing by the end of the Triassic. The basal split in Polyphaga was estimated to have occurred in the Triassic, with the stem groups of most series and superfamilies originating during the Triassic or Jurassic. Most extant families of beetles were estimated to have Cretaceous origins. Overall, Coleoptera experienced an increase in diversification rate compared to the rest of Neuropteroidea. Furthermore, 10 family-level clades, all in suborder Polyphaga, were identified as having experienced significant increases in diversification rate. These include most beetle species with phytophagous habits, but also several groups not typically or primarily associated with plants. Most of these groups originated in the Cretaceous, which is also when a majority of the most species-rich beetle families first appeared. An additional 12 clades showed evidence for significant decreases in diversification rate. These clades are species-poor in the Modern fauna, but collectively exhibit diverse trophic habits. The apparent success of beetles, as measured by species numbers, may result from their associations with widespread and diverse substrates -especially plants, but also including fungi, wood and leaf litter -but what facilitated these associations in the first place or has allowed these associations to flourish likely varies within and between lineages. Our results pr...

The discovery of Iberobaeniidae (Coleoptera: Elateroidea): a new family of beetles from Spain, with immatures detected by environmental DNA sequencing

“…However, these spurious relationships are a problem associated with the other sequences, not with Iberobaenia. Lissominae has a tendency to group with Lycidae [25], and close relatives of Mastinocerus (e.g. Rhagophthalmus) were never found with Lycidae in all previous analyses [8,13,25].…”

“…When Lycidae were excluded, the new taxon was recovered as the sister to elaterid subfamilies Thylacosterninae þ Lissominae, which have been difficult to place in molecular analyses (although placed in Elateridae based on morphology) and have a tendency to group with Lycidae using rRNA markers (e.g. [25]). The ML analyses of the mitogenome dataset recovered Iberobaenia in a clade containing besides Lycidae also Mastinocerus (Phengodidae) and Throscidae (electronic supplementary material, figure S4).…”

“…Analyses were repeated using the four partition schemes as before, applying a GTRþGþI substitution model as above and an uncorrelated lognormal clock to each partition [23]. Polyphaga were designated as sister to the remaining clades [24][25][26]. A Yule speciation prior was applied and analyses were run for 150 million generations sampling one tree every 5000 generations.…”

<strong><em>Cretonthophilus</em> <em>tuberculatus</em>, a remarkable new genus and species of hister beetle (Coleoptera: Histeridae) from Cretaceous Burmese amber</strong>

“…The presence of two such distinctive and derived forms indicates that Histeridae originated considerably earlier. At the same time, if the Histeridae split from the other Histeroidea ~120 mya as recent analyses indicate (McKenna et al, 2015b), then a rapid early diversification must be assumed.…”

The genus Brachypsectra LeConte, 1874 (Coleoptera: Brachypsectridae) in the Palaearctic Region

“…However, subsequent workers recognized this group as an independent family with close affinities to present-day Elateroidea (e.g., Blair 1930;Crowson 1973;Lawrence & Newton 1995), which has recently been confirmed by both morphological and molecular-based studies (Lawrence et al 2011;McKenna et al 2015).…”