Phylogenomic analysis of Apoidea sheds new light on the sister group of bees

Abstract

BackgroundApoid wasps and bees (Apoidea) are an ecologically and morphologically diverse group of Hymenoptera, with some species of bees having evolved eusocial societies. Major problems for our understanding of the evolutionary history of Apoidea have been the difficulty to trace the phylogenetic origin and to reliably estimate the geological age of bees. To address these issues, we compiled a comprehensive phylogenomic dataset by simultaneously analyzing target DNA enrichment and transcriptomic sequence data, comprising 195 single-copy protein-coding genes and covering all major lineages of apoid wasps and bee families.ResultsOur compiled data matrix comprised 284,607 nucleotide sites that we phylogenetically analyzed by applying a combination of domain- and codon-based partitioning schemes. The inferred results confirm the polyphyletic status of the former family “Crabronidae”, which comprises nine major monophyletic lineages. We found the former subfamily Pemphredoninae to be polyphyletic, comprising three distantly related clades. One of them, Ammoplanina, constituted the sister group of bees in all our analyses. We estimate the origin of bees to be in the Early Cretaceous (ca. 128 million years ago), a time period during which angiosperms rapidly radiated. Finally, our phylogenetic analyses revealed that within the Apoidea, (eu)social societies evolved exclusively in a single clade that comprises pemphredonine and philanthine wasps as well as bees.ConclusionBy combining transcriptomic sequences with those obtained via target DNA enrichment, we were able to include an unprecedented large number of apoid wasps in a phylogenetic study for tracing the phylogenetic origin of bees. Our results confirm the polyphyletic nature of the former wasp family Crabonidae, which we here suggest splitting into eight families. Of these, the family Ammoplanidae possibly represents the extant sister lineage of bees. Species of Ammoplanidae are known to hunt thrips, of which some aggregate on flowers and feed on pollen. The specific biology of Ammoplanidae as predators indicates how the transition from a predatory to pollen-collecting life style could have taken place in the evolution of bees. This insight plus the finding that (eu)social societies evolved exclusively in a single subordinated lineage of apoid wasps provides new perspectives for future comparative studies.Electronic supplementary materialThe online version of this article (10.1186/s12862-018-1155-8) contains supplementary material, which is available to authorized users.

Hybrid capture data unravel a rapid radiation of pimpliform parasitoid wasps (Hymenoptera: Ichneumonidae: Pimpliformes)

“…This number might seem low now, given that hundreds to thousands of genes are regularly sequenced to infer large phylogenies (dos Reis et al ., ; Misof et al ., ; Prum et al ., ; Bank et al ., ; Branstetter et al ., ; e.g. Peters et al ., ; Peters et al ., ; Sann et al ., ). However, the discussion triggered by this study (Phillips et al ., ; Collins et al ., ; Gatesy et al ., ) focused on two questions that are now more timely than ever: what are the causes of systematic biases in phylogenomics, and how many genes are really needed if they are chosen carefully?…”

DNA barcodes identify 99 per cent of apoid wasp species (Hymenoptera: Ampulicidae, Crabronidae, Sphecidae) from the Western Palearctic

“…Apoid wasps are traditionally classified in four families, Ampulicidae, Crabronidae, Heterogynaidae and Sphecidae. Although recent research suggests a new classification based on a phylogenomic analysis of the Apoidea with ten separate families (Sann et al, ), the present study uses the traditional classification with four families of apoid wasps, all except the Heterogynaidae are dealt with here. Together with the bees (Anthophila, consisting of seven families), they are usually subsumed under the superfamily Apoidea and belong to the megadiverse insect order Hymenoptera with currently more than 155,000 described species (Aguiar et al, ).…”

Low Host Specialization in the Cuckoo Wasp, Parnopes grandior, Weakens Chemical Mimicry but Does Not Lead to Local Adaption

“…The second hypothesis is that the P. grandior population is chemically more similar to just one of the three Bembix species, a strategy that could be explained by local adaptation. To test these hypotheses, we compared the CHCs profile of Bembix spp., P. grandior and a non-host "outgroup" species (Stizus continuus (Klug, 1835) belonging to the same tribe as Bembix (Bembicini) [31]. Furthermore, we performed behavioural assays to investigate whether the hosts can recognise the CHC profile of P. grandior.…”