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First evidence of attached juveniles in the solutan echinoderm Pahvanticystis from the middle Cambrian Weeks Formation (Utah, USA)
No full textThe fossil record of the Palaeozoic echinoderm class Soluta suggests they originated in the Miaolingian (middle Cambrian) of Laurentia as permanently attached suspension feeders, demonstrating a stepwise shift towards vagility in successive strata. Here, we report a new specimen of Pahvanticystis cf. utahensis associated with three putative juveniles interpreted as belonging to the same species. We interpret this as evidence of facultative attachment in juveniles of Pahvanticystis, which had not previously been reported in this taxon, but is known in the earlier genus Castericystis. Our findings indicate that attachment as a juvenile was more widespread in solutans than previously thought.Copyright © 2025 H.J. Savage and I.A. Rahman. This is an open-access article distributed under the terms of the Creative Commons Attribution License (for details please see http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The linked file is the published version of the article.NHM Repositor
The northernmost known observation of Myrmecophilus acervorum and the first records of Myrmecophilidae (Orthoptera, Ensifera) from Latvia
Get PDFThe first observations of myrmecophilous ant cricket Myrmecophilus acervorum (Panzer, 1799) and the family Myrmecophilidae from Latvia are presented. The observations were made in two locations subject to flooding in springtime. Adult and juvenile female individuals were observed. The discussed records appear to be the northernmost known distribution limit of this species.Copyright Aleksandrs Balodis et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricteduse, distribution, and reproduction in any medium, provided the original author and source are credited. The attached file is the published version of the article.NHM Repositor
Revisiting the genus Bolbosoma Porta, 1908 (Acanthocephala: Polymorphidae): host specificity, phylogeny, and species synonymization
Get PDFAbstract
Background: Acanthocephalans of the genus Bolbosoma Porta, 1908 are trophically transmitted parasites that infect marine mammals (mostly cetaceans and less frequently pinnipeds) worldwide. There are 12 species currently considered as valid; however, most records lack information on the maturity stage of the specimens. This, coupled with the scarce phylogenetic information available, hinders a correct understanding of their patterns of host specificity, evolutionary history, and taxonomy. A particularly intriguing case is that of Bolbosoma vasculosum (Rudolphi, 1819), which has been frequently reported in odontocetes but rarely as an adult, having been suggested to be synonymous with Bolbosoma capitatum (von Linstow, 1880).
Methods: We used a comprehensive approach to investigate the concept of Bolbosoma. First, we conducted a bibliographic review of records of Bolbosoma spp. to clarify which are the final hosts for each species. We paid particular attention to B. vasculosum, using morphological and molecular analyses to compare it with B. capitatum. Second, we characterized the complete mitochondrial genome of Bolbosoma balaenae (Gmelin, 1790), Bolbosoma turbinella (Diesing, 1851), B. capitatum, and B. vasculosum. Then, we reconstructed the phylogenetic relationships of Bolbosoma spp. and related taxa using full mitochondrial genomes (or only cox1 when full mitogenomes were unavailable) and nuclear ribosomal genes (18S and 28S).
Results: Bolbosoma spp. exhibit high specificity for cetaceans, with no confirmed records of adult specimens in other host groups. Within this genus, B. vasculosum appears to be conspecific with B. capitatum based on both morphological and molecular evidence. This species shows high affinity to odontocetes, while the remaining species are specific to mysticetes. Phylogenetic analyses showed strong support for the monophyly of Bolbosoma spp., which appeared as sister taxa to Corynosoma spp. and Andracantha spp.. The resulting topology aligns with the patterns of specificity indicated by host records, revealing two distinct clades for species specific to odontocetes and mysticetes, respectively.
Conclusions: The phylogenetic relationships obtained support the hypothesis that the association of Bolbosoma spp. with cetaceans originated through a host-switching event from aquatic birds.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
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mmons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. The attached file is the published version of the article
XX International Botanical Congress, Madrid 2024: Report of Congress action on nomenclature proposals
Get PDFCopyright © 2024 International Association for Plant Taxonomy. The attached file is the published version of the article.NHM Repositor
NEW AND POORLY-KNOWN TAXA OF LAGRIINAE LATREILLE, 1825 (COLEOPTERA: TENEBRIONIDAE) FROM THE COLLECTIONS OF THE NATURKUNDEMUSEUM ERFURT. 2
Get PDFIn the second paper of the series devoted to the study of lagriine material deposited at the Naturkundemuseum Erfurt, the following three species from the subtribe Lagriina Latreille, 1825, are described and illustrated: Lagria (s. str.) arfaka sp. nov., L. (s. str.) hatam sp. nov., L. (s. str.) undulata sp. nov. (all from New Guinea).The linked file is the published version of the article.NHM Repositor
Spatial controls on the generation of low-δ18O basalts on São Miguel, Azores
No full textVolcanism in the Azores is generally accepted to result from the decompression melting in the upper mantle associated with the Azorean plume. Basalts on the island of Sao ˜ Miguel have been previously recognised as having δ18O values lower than MORB with different authors ascribing this low-δ18O signature to either a component within the plume itself or as the result of assimilation of crustal materials at shallow level. Here we assess these contrasting models by using a suite of samples that are both geographically and temporally spread. We find that while low-δ18O mafic magmas (reaching 4.98 ‰) do occur on S˜
ao Miguel, they are spatially restricted to the Picos fissure system, between the central volcanoes of Sete Cidades and Fogo. Basalts of similar age from outside this restricted region return δ18O values that are similar to MORB. This spatial constraint argues that the source of the observed low-δ18O signature is within the crust rather than a component of the plume.
Previous studies on mafic to intermediate rocks of the Picos fissure system have identified the assimilation of broadly syenitic lithologies, which were found as co-erupted lithic clasts at the Fogo volcano and may have δ18O values as low as 2.6 ‰. However, trace element geochemistry indicates that these lithologies have not been assimilated within our low-δ18O samples, a more likely assimilant is altered oceanic crust or mafic lavas within the island edifice.Copyright © 2023 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). The linked file is the published version of the article.NHM Repositor
The explosive-effusive transition within the Miocene Fataga suite, Gran Canaria
No full textMany volcanoes show transitions between explosive and effusive eruptive styles both through the history of the volcano as a whole and occasionally within the course of a single eruption. These differing eruptive styles have vastly different implications for hazard assessments in surrounding regions and so understanding such changes is important. Here, we investigate the intercalated lavas and ignimbrites of the Miocene Fataga Group on the island of Gran Canaria, Spain. Ignimbrites reflect the products of explosive events from the Tejeda caldera, while lavas found within the pyroclastic succession were erupted from extra-caldera sources some 5–10 km from the caldera margin. The ignimbrites exhibit textural complexity containing both crystal-poor juvenile pyroclasts and late-erupted crystal-rich juvenile clasts interpreted to reflect interaction between cumulates and recharge magmas. The lavas meanwhile are almost phenocryst-free, with the exception of few large (cm-scale), unzoned sanidine crystals. Despite their textural differences, the lavas are geochemically similar (in terms of bulk rock and feldspar compositions) to the crystal-poor juveniles in the ignimbrites. Oxygen and lead isotopic compositions of the lavas and surrounding ignimbrites reveal that the magmas shared a deeper source and that petrographic variability is imprinted upon the magmas at shallow levels. We interpret the lavas as originating from peripheral magmatic pockets, on the edges of the main caldera-feeding reservoir. These peripheral magma chambers felt the effects of recharge only as slight thermal fluctuations that fostered the production of the large sanidine crystals. Our findings highlight the potential for storage of magmas aside from the main magmatic system that may represent an underappreciated hazard at volcanoes worldwide.Copyright © 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). The linked file is the published version of the article.NHM Repositor
Geochemistry of the Pepom tephra deposits: The most recent intracaldera volcanism of Sete Cidades volcano, São Miguel, Azores
Get PDFMany volcanoes have the ability to impact human infrastructure with explosive activity and understanding the processes of magma generation and conditions of storage in these systems remains a priority. The Sete Cidades volcano on the island of São Miguel, Azores archipelago is exactly such a volcano lying only 12 km from the island's capital city of Ponta Delgada and has been repeatedly active during the Holocene. Sete Cidades is the westernmost central volcano of São Miguel and its most recent explosive volcanism produced the Pepom series of 17 trachytic pumice deposits that were erupted from vents within the caldera. These variably magmatic and phreatomagmatic eruptions involved trachytic magmas that represent the end point of a magmatic evolution dominated by crystal fractionation processes. The magmas contain a mineral assemblage dominated by feldspar, with biotite, clinopyroxene, Fesingle bondTi oxides, amphibole, and trace apatite. Mineral thermometry and hygrometry reveal that the Pepom magmas were stored at temperatures of 789 ± 23 °C to 894 ± 20 °C under volatile-rich conditions (mostly >5 wt% water). Intercalated within the trachytic pyroclastic succession are mafic products that were erupted from vents on the flanks of the volcano suggesting that the evolved, shallow magmatic system may be acting as a barrier to ascending mafic magmas. The Pepom tephra deposits represent trachytic magmas that show limited evidence for the involvement of feldspar-dominated cumulates as has been observed in other settings whereas the preceding, caldera-forming, Santa Bárbara eruption suggests such involvement. Despite the predominant role of fractionation in petrogenesis, the Pepom tephras formed from mildly low-δ18O magmas (4.1 to 5.6‰ for trachyte) and as such require the addition of hydrothermally altered material. The cause of the low-δ18O values remains unknown, but low-δ18O, hydrothermally altered syenitic clasts found within deposits from the nearby Fogo volcano may be potentially analogues.Copyright © 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). The attached file is the published version of the article.NHM Repositor
The 2011 edition of “The Freshwater Algal Flora of the British Isles”: additions, corrections, nomenclatural and taxonomic changes
Get PDFTaxonomic, nomenclatural and distributional changes since the publication of the 2011 edition (reprinted 2021) of The Freshwater Algal Flora of the British Isles (“Flora”) are reviewed together with some changes overlooked earlier. Many of the more recent changes are a result of studies combining an analysis of morphological and DNA sequence data. Of the 473 changes reported most concern the Chlorophyta (131) and the Charophyta (156) followed by the Cyanobacteria (101), with most of the alterations to the Charophyta involving the desmids (136). Also included are 83 new additions to the British and Irish freshwater algal floras, including 20 overlooked in the Flora. Most of these additions are new records: four are newly described desmids and Synura hibernica (Ochrophyta, Chrysophyceae, Synurales) and Chlorococcum turfosum (Chlorophyta, Chlorophyceae, Chlamydomonadales) are also new. The new additions to Flora include information on locality, collector and publication source. Reference is made to discussions in the Flora giving reasons why some genera and species combinations were not accepted, particularly concerning the Cyanobacteria for which a relatively conservative approach had been adopted in
the previous edition of the Flora.Copyright © 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted 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
The genome sequence of the Dark Crimson Underwing moth, Catocala sponsa Linnaeus, 1767
Get PDFWe present a genome assembly from an individual female Catocala sponsa (the Dark Crimson Underwing; Arthropoda; Insecta; Lepidoptera; Erebidae). The genome sequence spans 803.70 megabases. Most of the assembly is scaffolded into 32 chromosomal pseudomolecules, including the Z and W sex chromosomes. The mitochondrial genome has also been assembled and is 15.57 kilobases in length. Gene annotation of this assembly on Ensembl identified 13,493 protein-coding genes.Copyright: © 2024 Broad GR et al. This is an open access article distributed under the terms of the Creative Commons Attribution
License, which permits unrestricted 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