Introduction: Historic museum collections hold a wealth of biodiversity data that are essential to our understanding of the rapidly changing natural world. Novel curatorial practices are needed to extract and digitise these data, especially for the innumerable pinned insects whose collecting information is held on small labels. Methods: We piloted semi-automated specimen imaging and digitisation of specimen labels for a collection of ~29,000 pinned insects of ground beetles (Carabidae: Lebiinae) held at the Natural History Museum, London. Raw transcription data were curated against literature sources and non-digital collection records. The primary data were subjected to statistical analyses to infer trends in collection activities and descriptive taxonomy over the past two centuries. Results: This work produced research-ready digitised records for 2,546 species (40% of known species of Lebiinae). Label information was available on geography in 91% of identified specimens, and the time of collection in 39.8% of specimens and could be approximated for nearly all specimens. Label data revealed the great age of this collection (average age 91.4 years) and the peak period of specimen acquisition between 1880 and 1930, with little differences among continents. Specimen acquisition declined greatly after about 1950. Early detected species generally were present in numerous specimens but were missing records from recent decades, while more recently acquired species (after 1950) were represented mostly by singleton specimens only. The slowing collection growth was mirrored by the decreasing rate of species description, which was affected by huge time lags of several decades to formal description after the initial specimen acquisition. Discussion: Historic label information provides a unique resource for assessing the state of biodiversity backwards to pre-industrial times. Many species held in historical collections especially from tropical super-diverse areas may not be discovered ever again, and if they do, their recognition requires access to digital resources and more complete levels of species description. A final challenge is to link the historical specimens to contemporary collections that are mostly conducted with mechanical trapping of specimens and DNA-based species recognition.

The trace fossil record provides important insights into the evolution of early animals during the Ediacaran/Cambrian transition, with changes in ichnodiversity through time and between environments informing on the diversification of major body plans, behaviors, and niches. To quantify variation in the diversity of trace fossils across this critical interval, we propose a measure of trace fossil dissimilarity (ichnodissimilarity) based on vector calculation. Furthermore, by comparing discrepancies between the angular bisector and mean vector of two sets of vectorized fossil data, we are able to weigh the relative contribution of increases and decreases in the variation of occurrences of taxa. We used this metric to analyze an expansive dataset of Ediacaran/Cambrian trace fossils. The results allowed us to quantify the diversification of traces across this transition, informing on the timing of first appearance of different behaviors (e.g., foraging, grazing, and resting) and functional groups. By interpreting the results in the context of environmental changes and advancements in motility and sensory capabilities, we were able to pinpoint the onset and sequence of the Fortunian diversification event, Cambrian information revolution, and agronomic revolution, shedding light on the evolution of organismal body plans, behaviors, and locomotion during the Ediacaran/Cambrian transition. We identified two phases of origination and expansion during the divergence of early animal traces. Furthermore, by analyzing shallow- and deep-marine trace fossils, we were able to uncover evidence for a more rapid diversification of traces in shallow-marine environments, with progressive niche partitioning through the Ediacaran to Cambrian.

We present a genome assembly from a specimen of <ns3:italic>Nanogona polydesmoides</ns3:italic> (eyed flat-backed millipede; Arthropoda; Diplopoda; Chordeumatida; Craspedosomatidae). The genome sequence has a total length of 406.26 megabases. Most of the assembly (95.49%) is scaffolded into 16 chromosomal pseudomolecules. The mitochondrial genome has also been assembled, with a length of 16.55 kilobases.

We present a genome assembly from a female specimen of <i>Lithobius variegatus</i> (banded centipede; Arthropoda; Chilopoda; Lithobiomorpha; Lithobiidae). The assembly contains two haplotypes with total lengths of 1,766.49 megabases and 1,768.00 megabases. Most of haplotype 1 (97.68%) is scaffolded into 23 chromosomal pseudomolecules. Haplotype 2 was assembled to scaffold level. The mitochondrial genome has also been assembled, with a length of 17.44 kilobases.

A sediment core (Core 19) taken in Daidokutsu cave on Ie Island, Okinawa, spans the last 7,000 years. The sampling of multiple taxa from this submarine cave has been aimed at understanding the Holocene history of biodiversity and ecological dynamics. The results have already been published for ostracods, molluscs, foraminifera and cheilostome bryozoans. The current study focuses on the cyclostome bryozoan fauna, establishing a taxonomic foundation that will contribute to an understanding of responses by the bryozoan community in this cave habitat to environmental and climate changes through the Holocene. Very little has been published on modern and Quaternary fossil cyclostomes from Japan, and nearly all publications predate the routine use of scanning electron microscopy in cyclostome taxonomy. Fifteen cyclostome species are described here from Daidokutsu. Eight of these are new species, the remaining seven were identified only to the genus level. The high proportion of new species may not only reflect the uniqueness of the Daidokutsu cyclostome fauna but also the scarcity of studies on Japanese cyclostomes and the inadequacy of descriptions and figures in older publications, which make it difficult or impossible to interpret the species they describe. Unlike cyclostome cave faunas from the Mediterranean, erect cyclostomes strongly outnumber species with encrusting colonies. In addition, the secondary homonymy of Parasmittina ligulata, used for both a new species from Daidokutsu Cave and a Western Atlantic species, is resolved by renaming the Japanese species Parasmittina vieirai nom. nov.

Abstract: Soil-transmitted helminths (STHs) are intestinal parasites that affect over a billion people worldwide. STH control relies on microscopy-based diagnostics to monitor parasite prevalence and enable post-treatment surveillance; however, molecular diagnostics are rapidly being developed due to increased sensitivity, particularly in low-STH-prevalence settings. The genetic diversity of helminths and its potential impact on molecular diagnostics remain unclear. Using low-coverage genome sequencing, we assess the genetics of STHs within worm, faecal, and purified egg samples from 27 countries, identifying differences in the genetic connectivity and diversity of STH-positive samples across regions and cryptic diversity between closely related human- and pig-infective species. We define substantial copy number and sequence variants in current diagnostic target regions and validate the impact of genetic variation on qPCR diagnostics using in vitro assays. Our study provides insights into the diversity and genomic epidemiology of STHs, highlighting both the challenges and opportunities for developing molecular diagnostics needed to support STH control efforts.

Ecdysozoans (Phyla Arthropoda, Kinorhyncha, Loricifera, Nematoda, Nematomorpha, Onychophora, Priapulida, Tardigrada) are invertebrates bearing a tough, periodically moulted cuticle that predisposes them to exceptional preservation. Ecdysozoans dominate the oldest exceptionally preserved bilaterian animal biotas in the early to mid-Cambrian (<jats:italic>c.</jats:italic> 520–508 Ma), with possible trace fossils in the latest Ediacaran (&lt;556 Ma). The fossil record of Ecdysozoa is among the best understood of major animal clades and is believed to document their origins and evolutionary history well. Strikingly, however, molecular clock analyses have implied a considerably deeper Precambrian origin for Ecdysozoa, much older than their earliest fossils. Here, using an improved set of fossil calibrations, we performed Bayesian analyses to estimate an evolutionary time-tree for Ecdysozoa, sampling all eight phyla for the first time. Our results recover Scalidophora as the sister group to Nematoida + Panarthropoda (= Cryptovermes nov.) and suggest that the Ediacaran divergence of Ecdysozoa occurred at least 23 myr before the first potential ecdysozoan trace fossils. This finding is impervious to the use of all plausible phylogenies, fossil prior distributions, evolutionary rate models and matrix partitioning strategies. Arthropods exhibit more precision and less incongruence between fossil- and clock-based estimates of clade ages than other ecdysozoan phyla. Supplementary material: Full methodologies used and an appendix of fossil calibration points are available at https://doi.org/10.6084/m9.figshare.c.5811381 Thematic collection: This article is part of the Advances in the Cambrian Explosion collection available at https://www.lyellcollection.org/cc/advances-cambrian-explosion

Cricocosmiidae is a clade of palaeoscolecid-like worms from the Chengjiang Biota, China (Cambrian Stage 3). In contrast with palaeoscolecids <jats:italic>sensu stricto</jats:italic>, which exhibit tessellating microplate trunk ornamentation, cricocosmiids have larger, serially repeated sets of trunk sclerites bearing a resemblance to lobopodian trunk sclerites (e.g. <jats:italic>Microdictyon</jats:italic> spp.). Cricocosmiidae have therefore been proposed as stem-group Panarthropoda in some studies, but are recovered as stem-group Priapulida in most phylogenetic analyses. The affinity of cricocosmiids within Ecdysozoa is therefore of much interest, as is testing the homology of these seriated structures. We report four new specimens of the rare cricocosmiid <jats:italic>Tabelliscolex hexagonus</jats:italic>, yielding new details of the ventral trunk projections, sclerites and proboscis. New data confirm that <jats:italic>T. hexagonus</jats:italic> had paired ventral trunk projections in a consistent seriated pattern, which is also reported from new material of <jats:italic>Cricocosmia jinningensis</jats:italic>(Cricocosmiidae) and <jats:italic>Mafangscolex yunnanensis</jats:italic> (Palaeoscolecida <jats:italic>sensu stricto</jats:italic>). Even when the seriated sclerites and ventral projections of cricocosmiids are coded as homologous with the seriated trunk sclerites and paired appendages, respectively, of lobopodian panarthropods, our tree searches indicate they are convergent. Cricocosmiidae is nested within a monophyletic ‘Palaeoscolecida <jats:italic>sensu lato</jats:italic>’ clade (Palaeoscolecidomorpha nov.) in stem-group Priapulida. Our study indicates that morphological seriation has independent origins in Scalidophora and Panarthropoda. Supplementary material: Phylogenetic character list and matrix are available at https://doi.org/10.6084/m9.figshare.c.5551565 Thematic collection: This article is part of the Advances in the Cambrian Explosion collection available at: https://www.lyellcollection.org/cc/advances-cambrian-explosion

Abstract: Cyanobacterial mats are commonly reported as hotspots of microbial diversity across polar environments. These thick, multilayered microbial communities provide a refuge from extreme environmental conditions, with many species able to grow and coexist despite the low allochthonous nutrient inputs. The visibly dominant phototrophic biomass is dependent on internal nutrient recycling by heterotrophic organisms within the mats; however, the specific contribution of heterotrophic protists remains little explored. In this study, mat community diversity was examined along a latitudinal gradient (55–83°N), spanning subarctic taiga, tundra, polar desert, and the High Arctic ice shelves. The prokaryotic and eukaryotic communities were targeted, respectively, by V4 16S ribosomal RNA (rRNA) and V9 18S rRNA gene amplicon high-throughput sequencing. Prokaryotic and eukaryotic richness decreased, in tandem with decreasing temperatures and shorter seasons of light availability, from the subarctic to the High Arctic. Taxonomy-based annotation of the protist community revealed diverse phototrophic, mixotrophic, and heterotrophic genera in all mat communities, with fewer parasitic taxa in High Arctic communities. Co-occurrence network analysis identified greater heterogeneity in eukaryotic than prokaryotic community structure among cyanobacterial mats across the Canadian Arctic. Our findings highlight the sensitivity of microbial eukaryotes to environmental gradients across northern high latitudes.

This commentary discusses a recent publication by evolutionary biologists with strong implications for migraine experts. The Authors showed that a gene polymorphism associated with migraine gave our ancestors an evolutionary advantage when colonizing northern, and thus colder, territories. They then highlight that the prevalence of migraine may differ among countries because of climatic adaptation. These results may prove useful in planning both epidemiological and physiological studies in the field of migraine.