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Gillett, C. P. D. T.

Publications and source records attributed to Gillett, C. P. D. T..

3 recordsLinked to original sources

Phylogenomics resolves a 200-year-old puzzle: a revised tribal classification of Afro-Eurasian dung beetles (Coleoptera: Scarabaeinae)

BackgroundThe tribal classification of scarab dung beetles (Coleoptera: Scarabaeinae) is currently largely incomplete due to the lack of robust phylogenetic evidence supporting the assignment of many Afro-Eurasian and American genera to tribes. MethodsWe used ultraconserved elements (UCEs) to infer phylogenetic relationships across most Afro-Eurasian dung beetle lineages, including 25 of the 27 extant genera currently incertae sedis. ResultsWe recovered full support for the monophyly of previously recognised tribes and for several phylogenetically and morphologically clearly delimited new tribal-level clades, allowing us to propose a complete tribal classification for all Afro-Eurasian dung beetle genera. Thirteen new tribes are described and diagnosed: Aphengoecini trib. nov., Bohepilissini trib. nov., Catharsiini trib. nov., Chalconotini trib. nov., Circelliini trib. nov., Dwesasilvasedini trib. nov., Haroldiini trib. nov., Heliocoprini trib. nov., Janssensantini trib. nov., Macroderini trib. nov., Nesovinsoniini trib. nov., Pycnopanelini trib. nov. and Tanzanolini trib. nov. The tribe Coprini sensu novo is redefined as comprising three subtribes: Coprina, Onychothecina subtrib. nov. and Pedariina subtrib. nov. The tribe Odontolomini is downranked to a subtribe of Endroedyolini sensu novo, becoming Endroedyolini Odontolomina stat. nov. The tribe Onthophagini sensu novo is redefined and divided into three subtribes: Helictopleurina stat. nov., Oniticellina stat. nov. and Onthophagina; the remaining former subtribes of Oniticellini (Attavicinina, Drepanocerina and Liatongina) are synonymised with Oniticellina; the subtribe Alloscelina of Onthophagini is synonymised with Onthophagina (syn. nov.). The tribe Panelini stat. rev. and sensu novo, comprising the single genus Panelus, is revalidated and redefined. Updated morphological diagnoses of Elassocanthonini, Gymnopleurini, Onitini and Scarabaeini are provided. The genus Phaedotrogus is synonymised with Haroldius (Haroldiini) (syn. nov.). An identification key to all Afro-Eurasian dung beetle tribes is provided. DiscussionOur results establish a robust phylogenetic framework and revised tribal classification for Afro-Eurasian Scarabaeinae dung beetles, providing a foundation for future taxonomic, comparative and macroevolutionary research.

zoology↗

Winners and Losers Among European Arthropods over the Last Half Century of Global Change

Widespread concern over arthropod declines has raised questions about how global change is reshaping biodiversity, yet large-scale responses within the group remain poorly understood. Here, we analyse 50 years (1970-2019) of European arthropod occurrence data to quantify distributional changes across more than 700 species within 11 taxonomic groups. Using occupancy-detection models that account for imperfect detection, we compare time-only and environmentally mediated trends, including changes to temperature, precipitation, and agricultural and urban land cover. We find no universal signal of decline; responses are highly heterogeneous, revealing distinct winners and losers both within and among groups. Climate variables, particularly temperature and precipitation, are the strongest predictors of change, while agricultural intensification is broadly negative and urbanisation produces group-specific effects. Trait analyses indicate that warm- and dry-affiliated species and larger-bodied arthropods generally fare better. These results show that recent European arthropod change is dominated by redistribution rather than uniform collapse, with important implications for conservation and monitoring under ongoing global change.

ecology↗

From museum drawer to tree: historical DNA phylogenomics clarifies the systematics of rare dung beetles (Coleoptera: Scarabaeinae) from museum collections

Although several methods exist for extracting and sequencing historical DNA originating from drypreserved insect specimens deposited in natural history museums, no consensus exists as to what is the optimal approach. We demonstrate that a customized, low-cost archival DNA extraction protocol ([~] {euro}10 per sample), in combination with Ultraconserved Elements (UCEs), is an effective tool for insect phylogenomic studies. We successfully tested our approach by sequencing DNA from scarab dung beetles preserved in both wet and dry collections, including unique primary type and rare historical specimens from internationally important natural history museums in London, Paris and Helsinki. The focal specimens comprise enigmatic dung beetle genera (Nesosisyphus, Onychotechus and Helictopleurus) that varied in age and preservation. The oldest specimen, the holotype of the now possibly extinct Mauritian endemic Nesosisyphus rotundatus, was collected in 1944. We obtained high-quality DNA from all studied specimens to enable the generation of a UCE-based dataset that revealed an insightful and well-supported phylogenetic tree of dung beetles. The resulting phylogeny suggested the reclassification of Onychotechus (previously incertae sedis) within the tribe Coprini. Our approach demonstrates the feasibility and effectiveness of combining DNA data from historic and recent museum specimens to provide novel insights. The proposed archival DNA protocol is available at DOI 10.17504/protocols.io.81wgbybqyvpk/v1 HighlightsO_LIWe combined custom low-cost archival DNA extractions and Ultraconserved Element phylogenomics C_LIO_LIDNA from rare museum specimens of enigmatic dung beetles revealed their phylogenetic connections C_LIO_LIGenomic data was obtained from the holotype of a potentially extinct monoinsular endemic species C_LIO_LIGenomic data allowed a rare and enigmatic species of previously unknown affinity to be classified C_LIO_LIThe morphology of museum specimens remained intact following non-destructive DNA extraction C_LI O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=80 SRC="FIGDIR/small/564347v1_ufig1.gif" ALT="Figure 1"> View larger version (24K): org.highwire.dtl.DTLVardef@34aad0org.highwire.dtl.DTLVardef@1ba597dorg.highwire.dtl.DTLVardef@1493c2dorg.highwire.dtl.DTLVardef@10dd2eb_HPS_FORMAT_FIGEXP M_FIG C_FIG

evolutionary biology↗