Biology subjects

Bocak, L.

Publications and source records attributed to Bocak, L..

6 recordsLinked to original sources

bioRxiv2026

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↗

bioRxiv2023

Ontogenetic modifications produce similar phenotypes in distantly related click beetles (Coleoptera: Elateridae)

The study analyzes the relationships of click beetles (Elateridae) Paulusiella Lobl, 2007, and Analestesa Leach, 1824 (=Cebriognathus Chobaut, 1899), both incapable of jumping, with soft-bodied habitus, and unknown females. Due to divergent morphology, their positions have been an uncertain issue. We use mitochondrial genomes to test their current placement in Cebrionini (=Cebriognathini) and Elaterinae incertae sedis, respectively. We recover Paulusiella as a sister to Hemiops Laporte, 1838 (Hemiopinae) and Analestesa as one of the serially splitting branches in Cardiophorinae, both with robust support. Paulusiellinae subfam. nov. is proposed for Paulusiella. Analestesa is transferred to Cardiophorinae, and Cebriognathini Paulus, 1981, an earlier synonym of Elaterinae: Cebrionini, is a synonym of Cardiophorinae Candeze, 1859. The click beetles affected by ontogenetic modifications converge to similar forms lacking derived states. As a result, their phylogenetic position cannot be reliably inferred by morphological analyses and needs to be validated by molecular data. Paulusiellinae and Analestesa represent two additional cases of the shift to incomplete sclerotization in elaterids raising the total number to six. The present transfers of extant taxa between subfamilies call for a cautious interpretation of morphology in other soft-bodied groups, including the taxa described from amber deposits.

zoology↗

bioRxiv2022

Neogene climatic fluctuations and poor connectivity with the centres of diversity shaped the Western Palearctic net-winged beetle fauna

Only twenty-two net-winged beetle species (Elateroidea: Lycidae) are known from the Western Palearctic region (WPR), i.e., less than 0.5% of the global lycid diversity and much fewer than from the similar latitudes of East Asia or Northern America. We use the comprehensive distribution data and the molecular phylogeny of [~]400 world lycids, including fourteen European species, to provide a new perspective for understanding the structure and evolution of this group in the WPR. All Mediterranean species represent deeply rooted lineages with relatives in Eastern Asia. These species occur in relictual ranges close to the familys Pleistocene refugial edge. The phylogeny points to the loss of biological connection with East Asia since the Mid Miocene. A third of WPR species is widespread in Central and Northern Europe, reaching Eastern Asia, some of them possibly younger elements of the European fauna. Unlike relatively high diversity in the Eocene amber, the extant net-winged beetles represent a small fraction of elateroid diversity in the WPR and are generally rare. Therefore, we assume that most WPR species are relics trapped in Mediterranean refugia since the onset of the Plio-Pleistocene cooling and are critically endangered by the ongoing loss of suitable habitats.

zoology↗

bioRxiv2021

Firefly bioluminescence outshines aerial predators

Bioluminescence is found across the tree of life and has many functions. Yet we understand very little about its timing and origins, particularly as a predator avoidance strategy. Understanding the timing between bioluminescence and predator origins has yet to be examined and can help elucidate the evolution of this ecologically important aposematic signal. Using the most prevalent bioluminescent group, fireflies, where bioluminescence primarily functions as aposematic and sexual signals, the timing for the origins of both potential predators of fireflies and bioluminescence is explored. Divergence time estimations were performed using genomic-scale phylogenetic reconstructions, and multiple fossil calibration points, allowing for a robust estimate for the origin of lampyrid bioluminescence as a terrestrial and as an aerial signal. Our results recover the origins of terrestrial beetle bioluminescence at 141.17 (122.63-161.17) mya and firefly aerial bioluminescence at 133.18 (117.86-152.47) mya with a large dataset focused on Lampyridae; and terrestrial bioluminescence as 148.03 (130.12-166.80) mya, with the age of aerial bioluminescence at 104.97 (99.00-120.90) mya with a complementary broad Elateroidea dataset. These ages predate the origins of all known extant aerial predators (i.e., bats and birds) and support the much older terrestrial predators (assassin bugs, frogs, ground beetles, lizards, snakes, hunting spiders, and harvestmen) as the most likely drivers of terrestrial bioluminescence in beetles, and sexual signaling likely being the original function in aerial fireflies.

evolutionary biology↗

bioRxiv2021

Phylogenomic and mitogenomic data can accelerate inventorying of tropical beetles during the current biodiversity crisis

Conservation efforts must be evidence-based, so rapid and economically feasible methods should be used to quantify diversity and distribution patterns. We have attempted to overcome current impediments to the gathering of biodiversity data by using integrative phylogenomic and three mtDNA fragment analyses. As a model, we sequenced the Metriorrhynchini beetle fauna, sampled from [~]700 localities in three continents. The species-rich dataset included [~]6,500 terminals, >2,300 putative species, more than a half of them unknown to science. The phylogenomic backbone enabled the integrative delimitation of robustly defined natural units that will inform future research. Using constrained mtDNA analysis, we identified the spatial structure of -diversity, very high species-level endemism, a biodiversity hotspot in New Guinea, and high phylogenetic diversity in the Sundaland. We suggest that [~]20 person months of focused field research and subsequent laboratory and bioinformatic workflow steps would substantially accelerate the inventorying of any hyperdiverse tropical group with several thousand species. The outcome would be a scaffold for the incorporation of further data. The database of sequences could set a benchmark for the spatiotemporal evaluation of biodiversity, would support evidence-based conservation planning, and would provide a robust framework for systematic, biogeographic, and evolutionary studies.

evolutionary biology↗

bioRxiv2018

The contribution of mitochondrial metagenomics to largescale data mining and phylogenetic analysis of Coleoptera

A phylogenetic tree at the species level is still far off for highly diverse insect orders, including the Coleoptera, but the taxonomic breadth of public sequence databases is growing. In addition, new types of data may contribute to increasing taxon coverage, such as metagenomic shotgun sequencing for assembly of mitogenomes from bulk specimen samples. The current study explores the application of these techniques for large-scale efforts to build the tree of Coleoptera. We used shotgun data from 17 different ecological and taxonomic datasets (5 unpublished) to assemble a total of 1942 mitogenome contigs of >3000 bp. These sequences were combined into a single dataset together with all mitochondrial data available at GenBank, in addition to nuclear markers widely used in molecular phylogenetics. The resulting matrix of nearly 16000 species with two or more loci produced trees (RAxML) showing overall congruence with the Linnaean taxonomy at hierarchical levels from suborders to genera. We tested the role of full-length mitogenomes in stabilizing the tree from GenBank data, as mitogenomes might link terminals with non-overlapping gene representation. However, the mitogenome data were only partly useful in this respect, presumably because of the purely automated approach to assembly and gene delimitation, but improvements in future may be possible by using multiple assemblers and manual curation. In conclusion, the combination of data mining and metagenomic sequencing of bulk samples provided the largest phylogenetic tree of Coleoptera to date, which represents a summary of existing phylogenetic knowledge and a defensible tree of great utility, in particular for studies at the intra-familial level, despite some shortcomings for resolving basal nodes.

evolutionary biology↗