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Linking monitoring data and timescales of mafic recharge during the 2013–17 eruption at Volcán de Colima, Mexico
No full textTimescales of mafic magma recharge beneath Volcán de Colima have been calculated from diffusion modelling of reversely zoned pyroxene crystals erupted in the 2013–17 interplinian eruptive period. The results suggest that injections of low volume mafic magma are periodic and ephemeral, residing in the plumbing system for only weeks to months before eruption. At least three separate periods of magma recharge and mixing occurred within c. 3 years in October 2013–April 2014, September 2014–June 2015 and November 2015–September 2016. These timescales have been compared with the continuous seismic monitoring of the volcano and quasi-continuous gas monitoring data. Each eruptive phase shows different patterns between petrological and monitoring data, suggesting a complex mixing-eruption relationship, which may be related to the frequency and volume of recharge events, as well as the thermal state of the magma reservoir. Low frequency or low volumes of magma injection may result in a lack of correlation with any change in the monitoring data. High frequency of magma injections priming the magma reservoir results in a strong correlation between recharge events and monitoring record, which may be useful for interpreting future monitoring data.Copyright © 2025 Published by Elsevier B.V. The linked file is the pre-proof version of the article. You are advised to consult the published version if you wish to cite from it.NHM Repositor
New insights into the evolutionary history of Fungi from a 407 Ma Blastocladiomycota fossil showing a complex hyphal thallus
Get PDFZoosporic fungi are key saprotrophs and parasites of plants, animals and other fungi, playing important roles in ecosystems. They comprise at least three phyla, of which two, Chytridiomycota and Blastocladiomycota, developed a range of thallus morphologies including branching hyphae. Here we describe Retesporangicus lyonii gen. et sp. nov., an exceptionally well preserved fossil, which is the earliest known to produce multiple sporangia on an expanded hyphal network. To better characterize the fungus we develop a new method to render surfaces from image stacks generated by confocal laser scanning microscopy. Here, the method helps to reveal thallus structure. Comparisons with cultures of living species and character state reconstructions analysed against recent molecular phylogenies of 24 modern zoosporic fungi indicate an affinity with Blastocladiomycota. We argue that in zoosporic fungi, kinds of filaments such as hyphae, rhizoids and rhizomycelium are developmentally similar structures adapted for varied functions including nutrient absorption and anchorage. The fossil is the earliest known type to develop hyphae which likely served as a saprotrophic adaptation to patchy resource availability. Evidence from the Rhynie chert provides our earliest insights into the biology of fungi and their roles in the environment. It demonstrates that zoosporic fungi were already diverse in 407 million-year-old terrestrial ecosystems.
This article is part of a discussion meeting issue ‘The Rhynie cherts: our earliest terrestrial ecosystem revisited’.Copyright © 2017 The Author(s) Published by the Royal Society. All rights reserved. The attached file is the published version of the article.NHM Repositor
Fertile Prototaxites taiti: a basal ascomycete with inoperculate, polysporous asci lacking croziers
Get PDFThe affinities of Prototaxites have been debated ever since its fossils, some attaining tree-trunk proportions, were discovered in Canadian Lower Devonian rocks in 1859. Putative assignations include conifers, red and brown algae, liverworts and fungi (some lichenised). Detailed anatomical investigation led to the reconstruction of the type species, P. logani, as a giant sporophore (basidioma) of an agaricomycete (= holobasidiomycete), but evidence for its reproduction remained elusive. Tissues associated with P. taiti in the Rhynie chert plus charcoalified fragments from southern Britain are investigated here to describe the reproductive characters and hence affinities of Prototaxites. Thin sections and peels (Pragian Rhynie chert, Aberdeenshire) were examined using light and confocal microscopy; Přídolí and Lochkovian charcoalified samples (Welsh Borderland) were liberated from the rock and examined with scanning electron microscopy. Prototaxites taiti possessed a superficial hymenium comprising an epihymenial layer, delicate septate paraphyses, inoperculate polysporic asci lacking croziers and a subhymenial layer composed predominantly of thin-walled hyphae and occasional larger hyphae. Prototaxites taiti combines features of extant Taphrinomycotina (Neolectomycetes lacking croziers) and Pezizomycotina (epihymenial layer secreted by paraphyses) but is not an ancestor of the latter. Brief consideration is given to its nutrition and potential position in the phylogeny of the Ascomycota.
This article is part of a discussion meeting issue ‘The Rhynie cherts: our earliest terrestrial ecosystem revisited’.Copyright © 2017 The Author(s) Published by the Royal Society. All rights reserved. The attached file is the published version of the article and is free access.NHM Repositor
The bulk mineralogy, elemental composition, and water content of the Winchcombe CM chondrite fall
Get PDFAbstract - On the microscale, the Winchcombe CM carbonaceous chondrite contains a number of lithological units with a variety of degrees of aqueous alteration. However, an understanding of the average hydration state is useful when comparing to other meteorites and remote observations of airless bodies. We report correlated bulk analyses on multiple subsamples of the Winchcombe meteorite, determining an average phyllosilicate fraction petrologic type of 1.2 and an average water content of 11.9 wt%. We show the elemental composition and distribution of iron and iron oxidation state are consistent with measurements from other CM chondrites; however, Winchcombe shows a low Hg concentration of 58.1 ± 0.5 ng g−1. We demonstrate that infrared reflectance spectra of Winchcombe are consistent with its bulk modal mineralogy, and comparable to other CM chondrites with similar average petrologic types. Finally, we also evaluate whether spectral parameters can estimate H/Si ratios and water abundances, finding generally spectral parameters underestimate water abundance compared to measured values.Copyright © 2023 The Authors. Meteoritics & Planetary Science published by Wiley Periodicals LLC on behalf of The Meteoritical Society. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. The attached file is the published version of the article.NHM Repositor
Creating a multi-linked dynamic dataset: a case study of plant genera named for women
Get PDFA discussion on social media led to the formation of a multidisciplinary group working on this project to highlight women’s contributions to science. The role of marginalised groups in science has been a topic of much discussion, but data on these contributions are largely lacking. Our motivation for the development of this dataset was not only to highlight names of plant genera that honour women, but to enrich this information with data that would allow the names, roles and lives of these women to be shared more widely with others, both researchers and data sources like Wikidata. Amplification of the contributions of women to botany through multiple means will enable the community to better recognise and celebrate the role of this particular marginalised group in the history and development of science.The innovative approach of our study resulted in a dataset that is dynamic, expansive and widely shared. We have published a static dataset with this paper and have also created a dynamic dataset by linking flowering plant genera and the women in whose honour those genera were named in Wikidata. This concurrent addition of the data to Wikidata, a linked open data repository, enabled it to be enriched, queried and proactively shared during the whole process of dataset creation and into the future. This innovative workflow allowed wide, open participation throughout the research process. The methodology and workflows applied can be used to create future datasets celebrating and amplifying the contributions of marginalised groups in science.</jats:p
Gregarious behaviour in Carboniferous cyclidan crustaceans
Get PDFGregarious behaviours in modern and fossil arthropods are commonly associated with defensive strategies, mass moulting and synchronous reproduction. Such behaviour is scarcely documented in the crustacean fossil record. Identifying clusters in extinct Pancrustacea is, therefore, important for understanding the evolutionary history and origin of crustacean gregariousness. Cyclida, an order of extinct, enigmatic pancrustaceans that have been subject to limited palaeoecological examination, represents an ideal group for testing the presence of gregarious behaviour. Here, we report a cluster of 50 Schramine montanaensis individuals from the Serpukhovian-aged Bear Gulch Limestone of Montana, USA, expanding the exceptionally rare record of cyclidan aggregations. The presence of articulated specimens with appendages and possible gill preservation supports the interpretation of carcasses that were preserved during a rapid burial event. We propose that this cluster records either a mass moulting event or clustering for shelter, representing one of the oldest records of crustacean gregariousness. These findings provide important insights into cyclidan life modes and ecological interactions in Carboniferous marine environments.Copyright © 2025 The Author(s). Published by the Royal Society. All rights reserved. The attached file is the published version of the article.NHM Repositor
Disporella guada sp. nov., an erect-ramose rectangulate cyclostome (Bryozoa, Stenolaemata) from the Carribean Sea: convergent evolution in bryozoan colony morphology
Get PDFThe taxonomy of cyclostome bryozoans is founded on characters of the skeleton, but molecular sequence data have increasingly shown that established higher taxa are not monophyletic. Here we describe the skeletal morphology of a new species from Guadeloupe (French West Indies) with erect ramose colonies consisting of long, curved zooids that are typical of the suborder Cerioporina among living cyclostomes. However, molecular evidence from nuclear ribosomal RNA genes 18S and 28S places the new taxon in the suborder Rectangulata, where this colony-form has not been previously recorded. It nests firmly within the genus Disporella Gray, 1848, in a strongly supported clade that also includes Plagioecia patina (Lamarck, 1816) (Tubuliporina) and the sister taxa Doliocoitis cyanea Gordon & Taylor, 2001 (Rectangulata) and Favosipora rosea Gordon & Taylor, 2001 (Cerioporina). The short and robust branches of the new Guadeloupe cyclostome, here named Disporella guada Harmelin, Taylor & Waeschenbach sp. nov., are well adapted to life in shallow rocky sites exposed to severe wave action, which appear to be its exclusive habitat.Copyright (c) 2021 Paul D. Taylor, Jean-Georges Harmelin, Andrea Waeschenbach, Claude Bouchon. Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License. The attached file is the published version of the article.NHM Repositor
Hominin glacial-stage occupation 712,000 to 424,000 years ago at Fordwich Pit, Old Park (Canterbury, UK)
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Few high-latitude archaeological contexts are older than marine isotope stage (MIS) 15 and even fewer provide evidence of early human occupation during a glacial period. New discoveries at Old Park, Canterbury (UK), provide evidence of both the oldest accessible artefact-bearing sediment in northern Europe and cold-stage adaptation. Radiometric and palaeomagnetic dating places the earliest suggested occupation of this site between 773 thousand years ago (ka) and 607 ka, with hominin presence inferred during MIS 17–16. Two additional artefact-bearing stratigraphic units, dated to around 542 ka and 437 ka, strongly align with the MIS 14 and 12 cold stages, respectively. The latter unit contains convincing evidence of glacial-stage occupation by Acheulean hominins; fresh, unabraded flakes (including biface-thinning) between clearly defined glacial-aged sediments displaying mixed grassland palaeoenvironmental evidence. An historically collected assemblage of more than 330 handaxes is argued to be derived from both the MIS 17–16 and MIS 12 sediments, providing evidence of the earliest known Acheulean bifaces in northern Europe, and re-occupation by Acheulean populations 200,000 years later. Together, Old Park provides evidence for Lower Palaeolithic hominins reoccupying a location over several mid-Pleistocene MIS cycles, early human presence above 51° latitude during a glacial stage and handaxe production in northern Europe from MIS 17 to 16.Copyright © The Author(s) 2025. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The attached file is the published version of the article.NHM Repositor
Struggling with shells: Drymaeus Albers, 1850 and Mesembrinus Albers, 1850 species (Mollusca, Gastropoda, Bulimulidae) from Peru—an illustrated checklist and descriptions of new species
Get PDFWe critically examine Peruvian taxa belonging to the genera Drymaeus Albers, 1850 and Mesembrinus Albers, 1850, verify their original reference, and figure type materials, if located in and available from museums. We include additional photographs of non-type material when they are deemed useful to show variation. Original figures from the literature are reproduced for some species where photographs of type material are unavailable. We list precise localities in Peru where each species has been collected and map each species. Where possible, the ecoregions in which each species occurs are indicated. A brief history of research on Drymaeus and Mesembrinus from Peru is included. We recognise 94 valid species of Drymaeus and Mesembrinus. Additionally, we list 10 taxa that have been erroneously or doubtfully reported from Peru, 10 that are nomina inquirandi, and four species that have been transferred to another genus. We believe that our checklist may serve as a baseline document for further research. It can be seen as an intermediate step in the revision of these genera, which will require additional anatomical or molecular study to achieve a stable classification.
The following new species are introduced: Drymaeus araujoi Vega-Luz, Breure & Mogollón; Drymaeus nebulosum Breure & Ablett; Mesembrinus marmoratus Breure, Mogollón & Vega-Luz; Mesembrinus purpuralabrum Breure, Mogollón & Vega-Luz.
Two species are reported from the Peruvian malacofauna for the first time: Drymaeus fusoides (d’Orbigny, 1835) and Drymaeus tigrinus (S.I. da Costa, 1898).
We propose the following new combinations: Drymaeus combinai (Weyrauch, 1958); Mesembrinus acobambensis (Weyrauch, 1967); Mesembrinus anceps (Albers, 1854); Mesembrinus angulobasis (Pilsbry, 1944); Mesembrinus apicepunctata (Preston, 1914); Mesembrinus bequaerti (Weyrauch, 1956); Mesembrinus cactivorus (Broderip, 1832); Mesembrinus chrysomelas (E. von Martens, 1867); Mesembrinus clathratus (L. Pfeiffer, 1858); Mesembrinus coelestini (F. Haas, 1952); Mesembrinus cuzcoensis (Reeve, 1849); Mesembrinus cylindricus (S.I. da Costa, 1901); Mesembrinus eucosmetus (F. Haas, 1955); Mesembrinus farrisi (L. Pfeiffer, 1858); Mesembrinus inconspicuus (F. Haas, 1949); Mesembrinus lamas (Higgins, 1868); Mesembrinus laxostylus (Rolle, 1904); Mesembrinus leucomelas (Albers, 1854); Mesembrinus libertadensis (Pilsbry, 1898); Mesembrinus mexicanus (Lamarck, 1822); Mesembrinus miltochrous (Albers, 1854); Mesembrinus nigroapicatus (L. Pfeiffer, 1857); Mesembrinus paeteli (Albers, 1854); Mesembrinus pergracilis (Rolle, 1904); Mesembrinus phryne (L. Pfeiffer, 1863); Mesembrinus praetextus (Reeve, 1849); Mesembrinus pseudobesus (Breure, 1979); Mesembrinus pulcherrimus (H. Adams, 1867); Mesembrinus rosalbus (Pilsbry, 1932); Mesembrinus sachsei (Albers, 1854); Mesembrinus scitulus (Reeve, 1849); Mesembrinus silvanus (Zilch, 1953); Mesembrinus succinea (Pilsbry, 1901); Mesembrinus trujillensis (Philippi, 1867); Mesembrinus vespertinus (L. Pfeiffer, 1858); Mesembrinus zilchi (F. Haas, 1955); “Mesembrinus” vexillum (W. Wood Sr, 1828).
The following junior subjective synonyms are established: Drymaeus aurantiostomus Thompson & Deisler, 1982 = Drymaeus branneri F. Baker, 1914; Drymaeus eusteirus Pilsbry, 1944 = Bulimus chanchamayensis Hidalgo, 1870; Drymaeus (Mormus) expansus flavilabrum Weyrauch, 1967 = Bulimus expansus L. Pfeiffer, 1848; Drymaeus (Orodrymaeus) farrisi quadritaeniatus Weyrauch, 1956 = Bulimus farrisi Pfeiffer, 1858; Drymaeus (Drymaeus) latitesta F. Haas, 1952 = Bulimus icterostomus E. von Martens, 1901; Drymaeus beyerleanus mitchelli Dall 1912 = Bulimus beyerleanus Hupé 1857; Bulimus (Liostracus) fuscobasis E.A. Smith, 1877 = Bulimus rectilinearis L. Pfeiffer, 1855; Bulimus recedens L. Pfeiffer, 1864 = Bulimus serratus L. Pfeiffer, 1855; Gonyostomus subhybridus S.I. da Costa, 1906 = Otostomus pulcherrimus H. Adams, 1867; Mesembrinus (Ornatimormus) henrypilsbryi densestrigatus Weyrauch, 1958 = Mesembrinus (Ornatimormus) henrypilsbryi pichitacalugaënsis Weyrauch 1958 = Mesembrinus (Ornatimormus) henrypilsbryi Weyrauch, 1958 = Bulimulus pergracilis Rolle, 1904; Bulimus canarius L. Pfeiffer, 1867 = Bulimus trujillensis Philippi, 1867; Bulimus serenus Philippi, 1867 = “Mesembrinus” vexillum (Wood, 1828).
The generic placements of “Drymaeus” expansus (L. Pfeiffer, 1848) and “Mesembrinus” vexillum (W. Wood Sr, 1828) are provisionally pending future molecular study.
The need for additional research is demonstrated by the fact that for 15 species only imprecise localities are known, while for 33 species no records are available within the last 50 years.Copyright ©The authors. This work is freely available under the Creative Commons Attribution 4.0 International licence (CC BY 4.0). The attached file is the published version of the article.NHM Repositor
Fossil evidence unveils an early Cambrian origin for Bryozoa
No full textAbstract - Bryozoans (also known as ectoprocts or moss animals) are aquatic, dominantly sessile, filter-feeding lophophorates that construct an organic or calcareous modular colonial (clonal) exoskeleton1–3. The presence of six major orders of bryozoans with advanced polymorphisms in lower Ordovician rocks strongly suggests a Cambrian origin for the largest and most diverse lophophorate phylum2,4–8. However, a lack of convincing bryozoan fossils from the Cambrian period has hampered resolution of the true origins and character assembly of the earliest members of the group. Here we interpret the millimetric, erect, bilaminate, secondarily phosphatized fossil Protomelission gatehousei9 from the early Cambrian of Australia and South China as a potential stem-group bryozoan. The monomorphic zooid capsules, modular construction, organic composition and simple linear budding growth geometry represent a mixture of organic Gymnolaemata and biomineralized Stenolaemata character traits, with phylogenetic analyses identifying P. gatehousei as a stem-group bryozoan. This aligns the origin of phylum Bryozoa with all other skeletonized phyla in Cambrian Age 3, pushing back its first occurrence by approximately 35 million years. It also reconciles the fossil record with molecular clock estimations of an early Cambrian origination and subsequent Ordovician radiation of Bryozoa following the acquisition of a carbonate skeleton10–13.This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. The attached file is the published version of the article.NHM Repositor