Phylogeny of the symphytan grade of Hymenoptera: new pieces into the old jigsaw(fly) puzzle

Abstract

The Hymenoptera constitutes one of the largest, and ecologically and economically most important, insect orders. During the past decade, a number of hypotheses on the phylogenetic relationships among hymenopteran families and superfamilies have been presented, based on analyses of molecular and/or morphological data. Nevertheless, many questions still remain, particularly concerning relationships within the hyperdiverse suborder Apocrita, but also when it comes to the evolutionary history of the ancestrally herbivorous "sawfly" lineages that form the basal, paraphyletic grade Symphyta. Because a large part of the uncertainty appears to stem from limited molecular and taxonomic sampling, we set out to investigate the phylogeny of Hymenoptera using nine protein-coding genes, of which five are new to analyses of the order. In addition, we more than tripled the taxon coverage across the symphytan grade, introducing representatives for many previously unsampled lineages. We recover a well supported phylogenetic structure for these early herbivorous hymenopteran clades, with new information regarding the monophyly of Xyelidae, the placement of the superfamily Pamphilioidea as sister to Tenthredinoidea + Unicalcarida, as well as the interrelationships among the tenthredinoid families Tenthredinidae, Cimbicidae, and Diprionidae. Based on the obtained phylogenies, and to prevent paraphyly of Tenthredinidae, we propose erection of the tribe Heptamelini to family status (Heptamelidae). In particular, our results give new insights into subfamilial relationships within the Tenthredinidae and other species-rich sawfly families. The expanded gene set provides a useful toolbox for future detailed analyses of symphytan subgroups, especially within the diverse superfamily Tenthredinoidea.

The genera of Nematinae (Hymenoptera, Tenthredinidae)

“…The root of the phylogenetic trees on Figs 2-5 was placed between Nematinae and other representatives of Tenthredinidae in the dataset. For the subfamilial phylogenetic relationships and placement of Nematinae within Tenthredinidae, see Malm and Nyman (2014).…”

The ghost of the Cretaceous terrestrial revolution in the evolution of fern–sawfly associations

“…This result may be caused by taxon sampling within the utilized phylogenetic framework, which focused on sampling representatives of distinct lineages instead of proportional representation of species diversity of sawflies (Malm & Nyman, 2015). Thus, denser sampling may be required to confirm that the observed "larval diet conservatism" is a result of monophylophagous genera utilizing, and perhaps coevolving with, ferns more frequently than expected in previous studies (Hendrix, 1980;Weintraub et al, 1995).…”

North-Western Palaearctic species of the Pristiphora ruficornis group (Hymenoptera, Tenthredinidae)

“…New COI primers were designed based on a broad sample of sawfly COI sequences available in NCBI GenBank (http://www.ncbi.nlm.nih.gov/genbank/) or BOLD (http:// www.boldsystems.org/), plus a few unpublished full COI sequences. New TPI primers were designed mainly based on four sawfly genomes and one transcriptome available in GenBank (accessions AOFN01004053, GAWW01005368, LGIB01000103, AMWH01006520, AZGP01000520) or using sequences published by Malm and Nyman (2015). Numbers in the new TPI primer names refer to the binding position of the primer's 3' end in the coding region of Athalia rosae mRNA (accession XM_012402337).…”