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Slipinski, A.

Publications and source records attributed to Slipinski, A..

3 recordsLinked to original sources

Time-calibrated phylogenomics reveals relationships and parallel evolution of neoteny within Elateriformia (Coleoptera) despite pervasive homoplasy

The controversy over Elateriformia relationships hampers understanding of the evolution of disparate soft-bodied and fully sclerotized phenotypes, bioluminescence, and the ontogenetic reprogramming that leads to larviform females. Elateriformia contains >50,000 species in 34 families, including fireflies, jewel, and click beetles. We sample 31 families and 195 ingroup taxa, each with up to 4,224 orthologs. Through explicit hypothesis testing, coalescent-based approaches, and evaluation of dataset properties, we resolve backbone relationships. We reconfirm the monophyly of Byrrhoidea sensu lato, rejecting the recent resurrection of Dryopoidea, and verify the reciprocally monophyletic lampyroid and elaterid clades. We characterize short internodes and gene-tree discordance, both of which are indicative of ancient rapid radiations. Counterintuitively, signals from moderately variable genes are crucial for resolving certain splits, suggesting that even subtle rate differences distinguish phylogenetically informative loci from overly conserved, less informative markers. Time-calibrated phylogenies indicate the early origin of Elateriformia (281-287 Mya), with superfamilies diverging at the Permian-Triassic boundary and diversifying throughout the Jurassic. We identify 15 independent origins of soft-bodiedness and neotenic modifications spanning the Mid Jurassic to the present. Our hypothesis provides a foundation for investigating the genetic mechanisms underlying ontogenetic reprogramming and bioluminescence.

evolutionary biology↗

Chromosome structural rearrangements in invasive haplodiploid ambrosia beetles revealed by the genomes of Euwallacea fornicatus and Euwallacea similis (Coleoptera, Curculionidae, Scolytinae)

Bark and ambrosia beetles are among the most ecologically and economically damaging introduced plant pests worldwide, with life history traits including polyphagy, haplodiploidy, inbreeding polygyny and symbiosis with fungi contributing to their dispersal and impact. Species vary in host tree ecologies, with many attacking stressed or recently dead trees, such as the globally distributed E. similis (Ferrari). Other species, like the Polyphagous Shot Hole Borer (PSHB) Euwallacea fornicatus (Eichhoff), can attack over 680 host plants and is causing considerable economic damage in several countries worldwide. Despite their notoriety, publicly accessible genomic resources for Euwallacea Hopkins species are scarce, hampering better understanding of their invasive capabilities as well as modern control measures, surveillance and management. Using a combination of long and short read sequencing platforms we assembled and annotated high quality (BUSCO > 98% complete) chromosome level genomes for these species. Comparative macro-synteny analysis showed an increased number of chromosomes in the haplodiploid inbreeding species of Euwallacea compared to diploid outbred species, due to fission events. This suggests that life history traits can impact chromosome structure. Further, the genome of E. fornicatus had a higher relative proportion of repetitive elements, up to 17% more, than E. similis. Additionally, metagenomic assembly pipelines identified microbiota associated with both species including Fusarium fungal symbionts and a novel Wolbachia strain. These novel genomes of haplodiploid inbreeding species will contribute to the understanding of how life history traits are related to their evolution and will contribute to the management of these invasive pests. SignificanceScolytinae are significant forestry pests around the world and commonly translocated due to human trade of wood and plant products. Life history traits including inbreeding and haplodiploidy are attributed to their successful establishment in novel environments. Euwallacea fornicatus is widely distributed and attacks a wide variety of live host trees. This study reports the genome of this species and for, E. similis, which colonises dead host trees. The genome assemblies presented herein are highly complete and scaffolded to pseudo-chromosomal level. Comparative analyses of these genomes and of other Scolytinae highlight significant chromosomal rearrangements between haplodiploid inbreeding Euwallacea and diploid outbreeding scolytinae species. Higher relative proportions of transposable elements were identified E. fornicatus, which may promote the species ability to attack live host trees. These genomes are the first for haplodiploid beetles and will contribute to the understanding of evolution of life history traits and the management of invasive insects.

genomics↗

Integrated phylogenomics and fossil data illuminate the evolution of beetles

With over 380,000 described species and possibly several million more yet unnamed, beetles represent the most biodiverse animal order. Recent phylogenomic studies have arrived at considerably incongruent topologies and widely varying estimates of divergence dates for major beetle clades. Here we use a dataset of 68 single-copy nuclear protein coding genes sampling 129 out of the 194 recognized extant families as well as the first comprehensive set of fully-justified fossil calibrations to recover a refined timescale of beetle evolution. Using phylogenetic methods that counter the effects of compositional and rate heterogeneity we recover a topology congruent with morphological studies, which we use, combined with other recent phylogenomic studies, to propose several formal changes in the classification of Coleoptera: Scirtiformia and Scirtoidea sensu nov., Clambiformia ser. nov. and Clamboidea sensu nov., Rhinorhipiformia ser. nov., Byrrhoidea sensu nov., Dryopoidea stat. res., Nosodendriformia ser. nov., and Staphyliniformia sensu nov., alongside changes below the superfamily level. The heterogeneous former superfamily Cucujoidea is divided into three monophyletic groups: Erotyloidea stat. nov., Nitiduloidea stat. nov., and Cucujoidea sensu nov. Our divergence time analysis recovered an evolutionary timescale congruent with the fossil record: a late Carboniferous origin of Coleoptera, a late Paleozoic origin of all modern beetle suborders, and a Triassic-Jurassic origin of most extant families. While fundamental divergences within beetle phylogeny did not coincide with the hypothesis of a Cretaceous Terrestrial Revolution, many polyphagan superfamilies exhibited increases in richness with Cretaceous flowering plants.

zoology↗