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Telenomus nizwaensis (Hymenoptera: Scelionidae), an important egg parasitoid of the pomegranate butterfly Deudorix livia Klug (Lepidoptera: Lycaenidae) in Oman
Get PDFThe pomegranate butterfly Deudorix ( Virachola) livia is the major pest of pomegranate, a crop of economic importance, in Oman. A species of parasitoid wasp in the hymenopteran family Scelionidae is responsible for high levels of mortality of its eggs. This wasp is described herein as Telenomus nizwaensis Polaszek sp. n., based on morphology and DNA sequence data. T. nizwaensis is currently known only from D. livia, which is also a pest of economic importance on other crops in North Africa, the Arabian Peninsula, and the Mediterranean. We summarise current knowledge of T. nizwaensis life-history and its potential to provide biological pest control.Copyright: © 2021 Polaszek 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 author and source are credited. The linked file is the published version of the article.NHM Repositor
Functional morphology of the Ediacaran organism Tribrachidium heraldicum
No full textAbstract: Tribrachidium heraldicum is an Ediacaran body fossil characterized by triradial symmetry. Previous work has suggested that the anatomy of Tribrachidium was conducive to passive suspension feeding; however, these analyses used an inaccurate model and a relatively simple set of simulations. Using computational fluid dynamics, we explore the functional morphology of Tribrachidium in unprecedented detail by gauging how the presence or absence of distinctive anatomical features (e.g., apical pits and arms) affects flow patterns. Additionally, we map particle pathways, quantify deposition rates at proposed feeding sites, and assess gregarious feeding habits to more fully reconstruct the lifestyle of this enigmatic taxon. Our results provide strong support for interpreting Tribrachidium as a macroscopic suspension feeder, with the apical pits representing loci of particle collection (and possibly ingestion) and the triradial arms representing morphological adaptations for interrupting flow and inducing settling. More speculatively, we suggest that the radial grooves may represent ciliated pathways through which food particles accumulating in the wake of the organism were transported toward the apical pits. Finally, our results allow us to generate new functional hypotheses for other Ediacaran taxa with a triradial body plan. This work refines our understanding of the appearance of suspension feeding in shallow-water paleoenvironments, with implications for the radiation of Metazoa across the Ediacaran/Cambrian boundary.Copyright © The Author(s), 2024. Published by Cambridge University Press on behalf of Paleontological Society. This is an Open
Access article, distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike licence
(http://creativecommons.org/licenses/by-ncsa/4.0), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the same Creative Commons licence is used to distribute the re-used or adapted article and the original article is properly cited. The written permission of Cambridge University Press must be obtained prior to any
commercial use. The linked file is the published version of the article.NHM Repositor
A fungal plant pathogen discovered in the Devonian Rhynie Chert
Get PDFAbstract: Fungi are integral to well-functioning ecosystems, and their broader impact on Earth systems is widely acknowledged. Fossil evidence from the Rhynie Chert (Scotland, UK) shows that Fungi were already diverse in terrestrial ecosystems over 407-million-years-ago, yet evidence for the occurrence of Dikarya (the subkingdom of Fungi that includes the phyla Ascomycota and Basidiomycota) in this site is scant. Here we describe a particularly well-preserved asexual fungus from the Rhynie Chert which we examined using brightfield and confocal microscopy. We document Potteromyces asteroxylicola gen. et sp. nov. that we attribute to Ascomycota incertae sedis (Dikarya). The fungus forms a stroma-like structure with conidiophores arising in tufts outside the cuticle on aerial axes and leaf-like appendages of the lycopsid plant Asteroxylon mackiei. It causes a reaction in the plant that gives rise to dome-shaped surface projections. This suite of features in the fungus together with the plant reaction tissues provides evidence of it being a plant pathogenic fungus. The fungus evidently belongs to an extinct lineage of ascomycetes that could serve as a minimum node age calibration point for the Ascomycota as a whole, or even the Dikarya crown group, along with some other Ascomycota previously documented in the Rhynie Chert.Copyright © The Author(s) 2023. 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 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. The linked document is the published version of the article.
holder. To view a copy of this license, visit http://creativecommons.org/
licenses/by/4.0/.NHM Repositor
Geology and fossils of Chatham Island, New Zealand
Get PDFThe attached file is the published version of the article.NHM Repositor
Identifying signatures of the earliest benthic bulldozers in emergent subaerial conditions during the colonization of land by animals
Get PDFThe colonization of land by animals was a milestone in the history of life. Approximately 100 million years before full terrestrialization, early animals sporadically traversed emergent subaerial substrates, leaving behind trace fossils recording their activities. However, identifying temporarily emergent environments and determining the affinities, motility and subaerial endurance of the trace-makers, and the timing and magnitude of their impacts on marginal-marine environments, are challenging. Here, we used semi-resolved computational fluid dynamics–discrete element method coupling to simulate trace formation on non-cohesive sediments in submerged and emergent subaerial conditions. This revealed instability-induced morphological signatures that allow us to identify the earliest terrestrial trace fossils. Quantitative metrics enable us to infer that the putative earliest terrestrial trace-makers were molluscs, and dimensional analysis suggests that their subaerial excursions could last at least 15 min. These organisms navigated emergent environments from the early Cambrian (stage 2), tens of millions of years earlier than arthropods. This quantitative paradigm provides new insights into the palaeobiology of the earliest subaerial bulldozers and highlights that mollusc-like animals were among the first ecosystem engineers to enter marginal-marine settings. They may thus have contributed to the establishment of marginal-marine biogeochemical cycles, laying the groundwork for subsequent terrestrialization by other animals.</jats:p
Intraspecific variation in the cochleae of harbour porpoises (Phocoena phocoena) and its implications for comparative studies across odontocetes
No full textIn morphological traits, variation within species is generally considered to be lower than variation among species, although this assumption is rarely tested. This is particularly important in fields like palaeontology, where it is common to use a single individual as representative of a species due to the rarity of fossils. Here, we investigated intraspecific variation in the cochleae of harbour porpoises (Phocoena phocoena). Interspecific variation of cochlear morphology is well characterised among odontocetes (toothed whales) because of the importance of the structure in echolocation, but generally these studies use only a single cochlea to represent each species. In this study we compare variation within the cochleae of 18 specimens of P. phocoena with variations in cochlear morphology across 51 other odontocete species. Using both 3D landmark and linear measurement data, we performed Generalised Procrustes and principal component analyses to quantify shape variation. We then quantified intraspecific variation in our sample of P. phocoena by estimating disparity and the coefficient of variation for our 3D and linear data respectively. Finally, to determine whether intraspecific variation may confound the results of studies of interspecific variation, we used multivariate and univariate analyses of variance to test whether variation within the specimens of P. phocoena was significantly lower than that across odontocetes. We found low levels of intraspecific variation in the cochleae of P. phocoena, and that cochlear shape within P. phocoena was significantly less variable than across odontocetes. Although future studies should attempt to use multiple cochleae for every species, our results suggest that using just one cochlea for each species should not strongly influence the conclusions of comparative studies if our results are consistent across Cetacea.Copyright © 2020 Martins et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ) and either DOI or URL of the article must be cited. The linked document is the published version of the article.NHM Repositor
Towards the analysis of coral skeletal density-banding using deep learning
Get PDFAbstract: X-ray micro–computed tomography (µCT) is increasingly used to record the skeletal growth banding of corals. However, the wealth of data generated is time consuming to analyse for growth rates and colony age. Here we test an artificial intelligence (AI) approach to assist the expert identification of annual density boundaries in small colonies of massive Porites spanning decades. A convolutional neural network (CNN) was trained with µCT images combined with manually labelled ground truths to learn banding-related features. The CNN successfully predicted the position of density boundaries in independent images not used in training. Linear extension rates derived from CNN-based outputs and the traditional method were consistent. In the future, well-resolved 2D density boundaries from AI can be used to reconstruct density surfaces and enable studies focused on variations in rugosity and growth gradients across colony 3D space. We recommend the development of a community platform to share annotated images for AI.Copyright © The Author(s) 2021. 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 linked document is the published version of the article.NHM Repositor
The genome sequence of the centipede Strigamia acuminata (Leach, 1816)
Get PDFWe present a genome assembly from an individual male Strigamia acuminata (centipede; Arthropoda; Chilopoda; Geophilomorpha; Geophilidae; Linotaeniinae). The genome sequence is 237.5 megabases in span. Most of the assembly is scaffolded into 11 chromosomal pseudomolecules, including the X and Y sex chromosomes. The mitochondrial genome has also been assembled and is 15.07 kilobases in length.Copyright: © 2023 Edgecombe GD 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
Bryozoa from the Maastrichtian Korojon Formation, Western Australia
No full textThe first Australian Cretaceous bryozoan fauna is described from the Upper Campanian – Lower Maastrichtian Korojon Formation from the Giralia Anticline in north-western Western Australia. Bryozoans are the numerically dominant element in
a sclerobiont community dependent on the abundant large inoceramids, utilizing both valves in life position as well as reworked shell fragments. A total of 68 species-level taxa are described (22 cyclostomes and 46 cheilostomes); 50 of these are new (12 cyclos-tomes and 38 cheilostomes) and the remaining 18 taxa are left at various levels of open nomenclature. They are referred to 47 genera (14 cyclostome and 33 cheilostome genera, 11 of which are new), with a total of 10 taxa left in open nomenclature. One new family, Cardabiellidae, is introduced. The total Late Cretaceous bryozoan fauna known from the Southern Hemisphere remnants of the Gondwana supercontinent – South America, Africa, India, Antarctica, Australia, Zealandia – is significantly less diverse than that known from the Northern Hemisphere, where the European Chalk Sea fauna constitutes the diversity hotspot. The addition of the Korojon fauna described here expands our knowledge of the Cretaceous bryozoan fauna from the Southern Hemisphere considerably, particularly with respect to the youngest bryozoan order, the Cheilostomata. And importantly, the Korojon fauna, more than doubles the proportion of Late Cretaceous cheilostome genera endemic to the Southern Hemisphere from 12.5% to more than 25% of the total number of Late Cretaceous genera presently known from this realm. We
suggest that this significant expansion may well warrant a reassessment of the role of Southern Hemisphere bryozoan faunas in the recovery from the Cretaceous-Paleogene biotic turnover.Copyright © Eckart Håkansson, Dennis P. Gordon and Paul D. Taylor 2024. The material in this publication is covered by the Norwegian Copyright Act and published open access under a Creative Commons CC BY 4.0 licence. The attached file is the published version of the article.NHM Repositor
NEW DATA ON DISTRIBUTION OF TWO PALAEARCTIC LEPTALEUS LAFERTÉ-SÉNECTÈRE, 1849 (COLEOPTERA: ANTHICIDAE) SPECIES WITH NEW RECORDS AND A CORRECTION
Get PDFNew country and regional records provided for Leptaleus chaudoiri (Kolenati, 1846), morphological variability of this species is discussed. Correction to the general distribution of L. uralensis (Pic, 1905) is reported.The attached file is the published version of the article.NHM Repositor