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Publications by Author: De Medeiros, Bruno A. S.

2024
Laurindo da Silva F, de Medeiros BAS, Farrell BD. Once upon a fly: The biogeographical odyssey of Labrundinia (Chironomidae, Tanypodinae), an aquatic non-biting midge towards diversification. Molecular Phylogenetics and Evolution. 2024;194 :108025.Abstract
Labrundinia is a highly recognizable lineage in the Pentaneurini tribe (Diptera, Chironomidae). The distinct predatory free-swimming larvae of this genus are typically present in unpolluted aquatic environments, such as small streams, ponds, lakes, and bays. They can be found on the bottom mud, clinging to rocks and wood, and dwelling among aquatic vegetation. Labrundinia has been extensively studied in ecological research and comprises 39 species, all but one of which has been described from regions outside the Palearctic. Earlier phylogenetic studies have suggested that the initial diversification of the genus likely occurred in the Neotropical Region, with its current presence in the Nearctic Region and southern South America being the result of subsequent dispersal events. Through the integration of molecular and morphological data in a calibrated phylogeny, we reveal a complex and nuanced evolutionary history for Labrundinia, providing insights into its biogeographical and diversification patterns. In this comprehensive study, we analyze a dataset containing 46 Labrundinia species, totaling 10,662 characters, consisting of 10,616 nucleotide sites and 46 morphological characters. The molecular data was generated mainly by anchored enrichment hybrid methods. Using this comprehensive dataset, we inferred the phylogeny of the group based on a total evidence matrix. Subsequently, we employed the generated tree for time calibration and further analysis of biogeography and diversification patterns. Our findings reveal multiple dispersal events out of the Neotropics, where the group originated in the late Cretaceous approximately 72 million years ago (69-78 Ma). We further reveal that the genus experienced an early burst of diversification rates during the Paleocene, which gradually decelerated towards the present-day. We also find that the Neotropics have played a pivotal role in the evolution of Labrundinia by serving as both a cradle and a museum. By "cradle," we mean that the region has been a hotspot for the origin and diversification of new Labrundinia lineages, while "museum" refers to the region's ability to preserve ancestral lineages over extended periods. In summary, our findings indicate that the Neotropics have been a key source of genetic diversity for Labrundinia, resulting in the development of distinctive adaptations and characteristics within the genus. This evidence highlights the crucial role that these regions have played in shaping the evolutionary trajectory of Labrundinia.
2021
Chamorro ML, de Medeiros BAS, Farrell BD. First phylogenetic analysis of Dryophthorinae (Coleoptera, Curculionidae) based on structural alignment of ribosomal DNA reveals Cenozoic diversification. Ecology and Evolution. 2021;11 (5). DOI (full text)Abstract
Abstract Dryophthorinae is an economically important, ecologically distinct, and ubiquitous monophyletic group of pantropical weevils with more than 1,200 species in 153 genera. This study provides the first comprehensive phylogeny of the group with the aim to provide insights into the process and timing of diversification of phytophagous insects, inform classification and facilitate predictions. The taxon sampling is the most extensive to date and includes representatives of all five dryophthorine tribes and all but one subtribe. The phylogeny is based on secondary structural alignment of 18S and 28S rRNA totaling 3,764 nucleotides analyzed under Bayesian and maximum likelihood inference. We used a fossil-calibrated relaxed clock model with two approaches, node-dating and fossilized birth-death models, to estimate divergence times for the subfamily. All tribes except the species-rich Rhynchophorini were found to be monophyletic, but higher support is required to ascertain the paraphyly of Rhynchophorini with more confidence. Nephius is closely related to Dryophthorini and Stromboscerini, and there is strong evidence for paraphyly of Sphenophorina. We find a large gap between the divergence of Dryophthorinae from their sister group Platypodinae in the Jurassic-Cretaceous boundary and the diversification of extant species in the Cenozoic, highlighting the role of coevolution with angiosperms in this group.
2020
de Medeiros BAS, Farrell BD. Evaluating insect-host interactions as a driver of species divergence in palm flower weevils. Communications Biology. 2020;3 (1) :749. DOI (full text)Abstract
Plants and their specialized flower visitors provide valuable insights into the evolutionary consequences of species interactions. In particular, antagonistic interactions between insects and plants have often been invoked as a major driver of diversification. Here we use a tropical community of palms and their specialized insect flower visitors to test whether antagonisms lead to higher population divergence. Interactions between palms and the insects visiting their flowers range from brood pollination to florivory and commensalism, with the latter being species that feed on decaying–and presumably undefended–plant tissues. We test the role of insect-host interactions in the early stages of diversification of nine species of beetles sharing host plants and geographical ranges by first delimiting cryptic species and then using models of genetic isolation by environment. The degree to which insect populations are structured by the genetic divergence of plant populations varies. A hierarchical model reveals that this variation is largely uncorrelated with the kind of interaction, showing that antagonistic interactions are not associated with higher genetic differentiation. Other aspects of host use that affect plant-associated insects regardless of the outcomes of their interactions, such as sensory biases, are likely more general drivers of insect population divergence.
2019
Fernández E, Ferreras I, Farrell BD, de Medeiros BAS, Romero-González GA. Studies in Aristolochia (Aristolochiaceae) of Hispaniola. Phytotaxa. 2019;420 :1-20. DOI (full text)Abstract
A review of the literature at large and the field photographic record of the senior author of this study indicate that there are several undescribed species of Aristolochia in Hispaniola (Dominican Republic and Haiti), related to A. bilobata. Here we show that A. mirandae is a synonym of A. bilobata and that what appears as A. bilobata in Marión H. (2011: 76–77) is a new species here described as Aristolochia adiastola. In addition, two new species, A. bonettiana and A. marioniana, also related to A. bilobata, are described and illustrated herein.
Church SH, Donoughe S, de Medeiros BAS, Extavour CG. A dataset of egg size and shape from more than 6,700 insect species. Sci Data. 2019;6 :104. DOI (Full text)Abstract
Offspring size is a fundamental trait in disparate biological fields of study. This trait can be measured as the size of plant seeds, animal eggs, or live young, and it influences ecological interactions, organism fitness, maternal investment, and embryonic development. Although multiple evolutionary processes have been predicted to drive the evolution of offspring size, the phylogenetic distribution of this trait remains poorly understood, due to the difficulty of reliably collecting and comparing offspring size data from many species. Here we present a dataset of 10,449 morphological descriptions of insect eggs, with records for 6,706 unique insect species and representatives from every extant hexapod order. The dataset includes eggs whose volumes span more than eight orders of magnitude. We created this dataset by partially automating the extraction of egg traits from the primary literature. In the process, we overcame challenges associated with large-scale phenotyping by designing and employing custom bioinformatic solutions to common problems. We matched the taxa in this dataset to the currently accepted scientific names in taxonomic and genetic databases, which will facilitate the use of these data for testing pressing evolutionary hypotheses in offspring size evolution.
Church SH, Donoughe S, de Medeiros BAS, Extavour CG. Insect egg size and shape evolve with ecology but not developmental rate. Nature. 2019;571 :58-62. DOI (full text)Abstract
Over the course of evolution, organism size has diversified markedly. Changes in size are thought to have occurred because of developmental, morphological and/or ecological pressures. To perform phylogenetic tests of the potential effects of these pressures, here we generated a dataset of more than ten thousand descriptions of insect eggs, and combined these with genetic and life-history datasets. We show that, across eight orders of magnitude of variation in egg volume, the relationship between size and shape itself evolves, such that previously predicted global patterns of scaling do not adequately explain the diversity in egg shapes. We show that egg size is not correlated with developmental rate and that, for many insects, egg size is not correlated with adult body size. Instead, we find that the evolution of parasitoidism and aquatic oviposition help to explain the diversification in the size and shape of insect eggs. Our study suggests that where eggs are laid, rather than universal allometric constants, underlies the evolution of insect egg size and shape.
Valente RM, Da Silva PAL, de Medeiros BAS. The first species of Cotithene Voss (Coleoptera: Curculionidae: Curculioninae) from Amazonian Brazil, with notes on its role as a pollinator of Evodianthus funifer (Poit.) Lindm. (Cyclanthaceae). Zootaxa. 2019;4576 :461.
de Medeiros BAS, Núñez-Avellaneda LA, Hernandez AM, Farrell BD. Flower visitors of the licuri palm (Syagrus coronata): brood pollinators coexist with a diverse community of antagonists and mutualists. Biological Journal of the Linnean Society. 2019.
2018
McKenna DD, Clarke D, Anderson R, Astrin J, Brown S, Chamorro L, Davis S, de Medeiros BAS, del Rio M, Haran J, et al. Morphological and Molecular Perspectives on the Phylogeny, Evolution, and Classification of Weevils (Coleoptera: Curculionoidea): Proceedings from the 2016 International Weevil Meeting. Diversity. 2018;10 :64.
de Medeiros BAS, Farrell BD. Whole-genome amplification in double-digest RADseq results in adequate libraries but fewer sequenced loci. PeerJP. 2018;(6) :e5089. DOI (full text)Abstract
Whole-genome amplification by multiple displacement amplification (MDA) is a promising technique to enable the use of samples with only limited amount of DNA for the construction of RAD-seq libraries. Previous work has shown that, when the amount of DNA used in the MDA reaction is large, double-digest RAD-seq (ddRAD) libraries prepared with amplified genomic DNA result in data that are indistinguishable from libraries prepared directly from genomic DNA. Based on this observation, here we evaluate the quality of ddRAD libraries prepared from MDA-amplified genomic DNA when the amount of input genomic DNA and the coverage obtained for samples is variable. By simultaneously preparing libraries for five species of weevils (Coleoptera, Curculionidae), we also evaluate the likelihood that potential contaminants will be encountered in the assembled dataset. Overall, our results indicate that MDA may not be able to rescue all samples with small amounts of DNA, but it does produce ddRAD libraries adequate for studies of phylogeography and population genetics even when conditions are not optimal. We find that MDA makes it harder to predict the number of loci that will be obtained for a given sequencing effort, with some samples behaving like traditional libraries and others yielding fewer loci than expected. This seems to be caused both by stochastic and deterministic effects during amplification. Further, the reduction in loci is stronger in libraries with lower amounts of template DNA for the MDA reaction. Even though a few samples exhibit substantial levels of contamination in raw reads, the effect is very small in the final dataset, suggesting that filters imposed during dataset assembly are important in removing contamination. Importantly, samples with strong signs of contamination and biases in heterozygosity were also those with fewer loci shared in the final dataset, suggesting that stringent filtering of samples with significant amounts of missing data is important when assembling data derived from MDA-amplified genomic DNA. Overall, we find that the combination of MDA and ddRAD results in high-quality datasets for population genetics as long as the sequence data is properly filtered during assembly.
Kim SI, de Medeiros BAS, Byun B-K, Lee S, Kang J-H, Lee B, Farrell BD. West meets East: How do rainforest beetles become circum-Pacific? Evolutionary origin of Callipogon relictus and allied species (Cerambycidae: Prioninae) in the New and Old Worlds. Molecular Phylogenetics and Evolution. 2018;125 :163-176. DOI (full text)Abstract
The longhorn beetle genus Callipogon Audinet-Serville represents a small group of large wood-boring beetles whose distribution pattern exhibits a unique trans-Pacific disjunction between the East Asian temperate rainforest and the tropical rainforest of the Neotropics. To understand the biogeographic history underlying this circum-Pacific disjunct distribution, we reconstructed a molecular phylogeny of the subfamily Prioninae with extensive sampling of Callipogon using multilocus sequence data of 99 prionine and four parandrine samples (ingroups), together with two distant outgroup species. Our sampling of Callipogon includes 18 of the 24 currently accepted species, with complete representation of all species in our focal subgenera. Our phylogenetic analyses confirmed the purported affinity between the Palearctic Callipogon relictus and its Neotropical congeners. Furthermore, based on molecular dating under the fossilized birth-death (FBD) model with comprehensive fossil records and probabilistic ancestral range reconstructions, we estimated the crown group Callipogon to have originated in the Paleocene circa 60 million years ago (Ma) across the Neotropics and Eastern Palearctics. The divergence between the Palearctic C. relictus and its Neotropical congeners is explained as the result of a vicariance event following the demise of boreotropical forest across Beringia at the Eocene-Oligocene boundary. As C. relictus represents the unique relictual species that evidentiates the lineage's expansive ancient distribution, we evaluated its conservation importance through species distribution modelling. Though we estimated a range expansion for C. relictus by 2050, we emphasize a careful implementation of conservation programs towards the protection of primary forest across its current habitats, as the species remains highly vulnerable to habitat disturbance.
2017
de Medeiros BAS, Barghini A, Vanin SA. Streetlights attract a broad array of beetle species. Revista Brasileira de Entomologia. 2017;61 (1) :74 - 79. DOI (full text)Abstract
Light pollution on ecosystems is a growing concern, and knowledge about the effects of outdoor lighting on organisms is crucial to understand and mitigate impacts. Here we build up on a previous study to characterize the diversity of all beetles attracted to different commonly used streetlight set ups. We find that lights attract beetles from a broad taxonomic and ecological spectrum. Lights that attract a large number of insect individuals draw an equally high number of insect species. While there is some evidence for heterogeneity in the preference of beetle species to different kinds of light, all species are more attracted to some light radiating ultraviolet. The functional basis of this heterogeneity, however, is not clear. Our results highlight that control of ultraviolet radiation in public lighting is important to reduce the number and diversity of insects attracted to lights.
deMedieros_streetlights_beetles.pdf
2014
de Medeiros BAS, Bena DD, Vanin SA. Curculio Curculis lupus: biology, behavior and morphology of immatures of the cannibal weevil Anchylorhynchus eriospathae G. G. Bondar, 1943. Peerj. 2014;2. DOI (full text)Abstract

Weevils are one of the largest groups of living organisms, with more than 60,000 species feeding mostly on plants. With only one exception, their described larvae are typical plant-feeders, with mouthparts adapted to chewing plant material. Here we describe the second case of a weevil with early-instar larvae adapted to killing conspecifics. We have studied the life history of Anchylorhynchus eriospathae G. G. Bondar, 1943 (Curculioninae: Derelomini sensu Caldara, Franz & Oberprieler (2014)), a species whose immatures feed internally on palm flowers and fruits. We provide detailed descriptions of all immature stages, including the extremely modified first-instar larva. Unlike other weevils and later instars, this stage exhibits a flat body with very long ventropedal lobe setae, a large and prognathous head with a gula, and falciform mandibles, each with a serrate retinaculum, that are used to fight with and eventually kill other first-instar larvae. We also provide biological notes on all stages and the results of behavioral tests that showed that larval aggression occurs only among early life stages. Finally we show that adult size is highly dependent on timing of oviposition. This specialized killer first instar probably evolved independently from the one other case known in weevils, in Revena rubiginosa (Conoderinae: Bariditae sensu Prena, Colonnelli & Hespenheide (2014)). Interestingly, both lineages inhabit the same hosts, raising the possibility that both intra-and inter-specific competition shaped those phenotypes. Given the scarcity of knowledge on early larval stages of concealed insect herbivores, it is possible that our findings represent an instance of a much broader phenomenon. Our observations also allowed us to conclude that Anchylorhynchus eriospathae and A. hatschbachi G. G. Bondar, 1943 are actually the same species, which we synonymize here by considering the latter as a junior synonym(new synonymy).

2013
Valente RD, de Medeiros BAS. A new species of Anchylorhynchus Schoenherr (Coleoptera: Curculionidae) from the Amazon, with a record of a new host palm for the genus. Zootaxa. 2013;3709 (4) :394-400. DOI (full text)Abstract

Anchylorhynchus vanini sp. nov. from the Amazon is described, including the mouthparts and male genitalia. The new species is compared with similar species within the genus and the key to the species of Anchylorhynchus provided by Vaurie (1954) is modified to include the new species. Adult specimens were collected in flowers of the palm Syagrus vermicularis Noblick and additional collections in other palms species suggest that this association is specific. This is the first record of the palm Syagrus vermicularis as host for a species of Anchylorhynchus.

Vanin SA, de Medeiros BAS. A new species of Sicoderus Vanin from Bolivia (Coleoptera: Curculionidae: Curculioninae: Otidocephalini). Zootaxa. 2013;3734 (1) :81-85. DOI (full text)Abstract

Sicoderus robini sp. nov. (type locality: Bolivia, Santa Cruz de la Sierra, Buena Vista, El Cairo) is described and illustrated. The new species is assigned to the Sicoderus appendiculatus species group, compared with similar species of the group and with the two other species of Sicoderus that occur in Bolivia. The previously published key for species identification of the S. appendiculatus group is updated to include the new species.

de Medeiros BAS, Núñez-Avellaneda LA. Three new species of Anchylorhynchus Schoenherr, 1836 from Colombia (Coleoptera: Curculionidae; Curculioninae; Acalyptini). Zootaxa. 2013;3636 (2) :394-400. DOI (full text)Abstract

Three new species of the genus Anchylorhynchus from Colombia, are described: Anchylorhynchus pinocchio sp. nov., A. centrosquamatus sp. nov. and A. luteobrunneus sp. nov.. A morphological description, including the male genitalia, is provided for each species as well as a comparison with similar species within the genus. All three species are found in inflorescences of species of Syagrus Mart. (Arecaceae). The adults are pollinators and the larvae develop inside fruits and feed on the endosperm, interrupting seed formation and causing fruit abortion.

2012
Barghini A, de Medeiros BAS. UV Radiation as an Attractor for Insects. Leukos. 2012;9 (1) :47-56. Publisher's VersionAbstract

Light pollution due to exterior lighting is a rising concern. While glare, light trespass and general light pollution have been well described, there are few reported studies on the impact of light pollution on insects. By studying insect behavior in relation to artificial lighting, we suggest that control of the UV component of artificial lighting can significantly reduce its attractiveness, offering a strong ability to control the impact on insects. Traditionally, the attractiveness of a lamp to insects is calculated using the luminous efficiency spectrum of insect rhodopsin. This has enabled the development of lamps that emit radiation with wavelengths that are less visible to insects (that is, yellow lamps). We tested the assumption that the degree of visibility of a lamp to insects can predict its attractiveness by means of experimental collections. We found that the expected lamp's visibility is indeed related to the extent to which it attracts insects. However, the number of insects attracted to a lamp is disproportionally affected by the emission of ultraviolet radiation. UV triggers the behavior of approaching lights more or less independently of the amount of UV radiation emitted. Thus, even small amounts of UV should be controlled in order to develop bug-free lamps.