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The cranial morphology of Tanystropheus hydroides (Tanystropheidae, Archosauromorpha) as revealed by synchrotron microtomography
Get PDFThe postcranial morphology of the extremely long-necked Tanystropheus hydroides is well-known, but observations of skull morphology were previously limited due to compression of the known specimens. Here we provide a detailed description of the skull of PIMUZ T 2790, including a partial endocast and endosseous labyrinth, based on synchrotron microtomographic data, and compare its morphology to that of other early Archosauromorpha. In many features, such as the wide and flattened snout and the configuration of the temporal and palatal regions, Tanystropheus hydroides differs strongly from other early archosauromorphs. The braincase possesses a combination of derived archosaur traits, such as the presence of a laterosphenoid and the ossification of the lateral wall of the braincase, but also differs from archosauriforms in the morphology of the ventral ramus of the opisthotic, the horizontal orientation of the parabasisphenoid, and the absence of a clearly defined crista prootica. Tanystropheus hydroides was a ram-feeder that likely caught its prey through a laterally directed snapping bite. Although the cranial morphology of other archosauromorph lineages is relatively well-represented, the skulls of most tanystropheid taxa remain poorly understood due to compressed and often fragmentary specimens. The recent descriptions of the skulls of Macrocnemus bassanii and now Tanystropheus hydroides reveal a large cranial disparity in the clade, reflecting wide ecological diversity, and highlighting the importance of non-archosauriform Archosauromorpha to both terrestrial and aquatic ecosystems during the Triassic.© 2020 Spiekman 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.NHM Repositor
Calathus: A sample-return mission to Ceres
Get PDFCeres, as revealed by NASA's Dawn spacecraft, is an ancient, crater-saturated body dominated by low-albedo clays. Yet, localised sites display a bright, carbonate mineralogy that may be as young as 2 Myr. The largest of these bright regions (faculae) are found in the 92 km Occator Crater, and would have formed by the eruption of alkaline brines from a subsurface reservoir of fluids. The internal structure and surface chemistry suggest that Ceres is an extant host for a number of the known prerequisites for terrestrial biota, and as such, represents an accessible insight into a potentially habitable “ocean world”. In this paper, the case and the means for a return mission to Ceres are outlined, presenting the Calathus mission to return to Earth a sample of the Occator Crater faculae for high-precision laboratory analyses. Calathus consists of an orbiter and a lander with an ascent module: the orbiter is equipped with a high-resolution camera, a thermal imager, and a radar; the lander contains a sampling arm, a camera, and an on-board gas chromatograph mass spectrometer; and the ascent module contains vessels for four cerean samples, collectively amounting to a maximum 40 g. Upon return to Earth, the samples would be characterised via high-precision analyses to understand the salt and organic composition of the Occator faculae, and from there to assess both the habitability and the evolution of a relict ocean world from the dawn of the Solar System.The attached document is the authors’ final accepted version of the journal article provided here with a Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) Creative Commons Licence. You are advised to consult the publisher’s version if you wish to cite from it.’NHM Repositor
Lappet-faced Vultures with white feathers
Get PDFThis is an open access article, available to all readers online. The attached file is the published version of the article.NHM Repositor
Isotopic and textural analysis of giant unmelted micrometeorites – identification of new material from intensely altered 16O-poor water-rich asteroids
Get PDFBulk oxygen isotope data has the potential to match extraterrestrial samples to parent body sourcesbased on distinctive 18O and Δ 17 O ratios. We analysed 10 giant (>500µm) micrometeorites using combined µCT and O-isotope analysis to pair internal textures to inferred parent body groups. We identify three ordinary chondrite particles (L and LL groups), four from CR chondrites and the first micrometeorite from the enstatite chondrite (EH4) group. In addition, two micrometeorites are from
hydrated carbonaceous chondrite parent bodies with 16 O-poor isotopic compositions above the terrestrial fractionation line. They experienced intense aqueous alteration, contain pseudomorphic chondrules and are petrographically similar to the CM1/CR1 chondrites. These micrometeorites may be members of the newly established CY chondrites and/or derived from the enigmatic “Group 4” micrometeorite population, previously identified by Yada et al., 2005 [GCA, 69:5789-5804], Suavet et
al., 2010 [EPSL, 293:313-320] (and others). One of our 16 O-poor micrometeorite plots on the same isotopic trendline as the CO, CM and CY chondrites – “the CM mixing line” (with a slope of ~0.7 and a 17 O intercept of -4.23‰), implies a close relationship and potentially a genetic link to these hydrated chondrites. If position along the CM mixing line reflects the amount of 16 O-poor (heavy) water-ice accreted onto the parent body at formation, then the CY chondrites and these 16 O-poor micrometeorites must have accreted at least as much water-ice as CM chondrites but potentially more. In addition, thermal metamorphism could have played a role in further raising the bulk O isotope compositions through the preferential loss of isotopically light water during phyllosilicate dehydration. The study of micrometeorites provides insights into asteroid belt diversity through the discovery of material not currently sampled by larger meteorites, perhaps as a result of atmospheric entry biases preventing the survival of large blocks of friable hydrated material.Copyright © 2021, Suttle MD, et al. This document is the author’s final accepted version of the journal article. You are advised to consult the published version if you wish to cite from it.NHM Repositor
The first fossil Coleoptera record from the Volyn Region, Ukraine, with description of a new Glesoconomorphus (Coleoptera, Mycteridae) in syninclusion with Winterschmidtiidae (Acari) and a key to species
Get PDFGlesoconomorphus ekaterinae sp. nov. (Coleoptera, Mycteridae), representing the first ever fossil species of Coleoptera from the Volyn Region of Ukraine and the first mycterid from late Eocene Rovno amber, is described and illustrated. A key to species of the fossil mycterid genus Glesoconomorphus Alekseev, Pollock & Bukejs, 2019 is presented. The systematic position of Glesoconomorphus within Eurypinae J. Thomson, 1860 is briefly discussed. The oldest finding of phoretic Winterschmidtiidae Oudemans, 1923 mites, found on the type specimen of the new beetle species, is reported.Copyright Dmitry Telnov et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CCBY 4.0), which permits unrestricted use, 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
Review of the genus Dinetus Panzer, 1806 (Hymenoptera: Crabronidae: Dinetinae) with descriptions of new subgenera and new species
No full textOne new species of Dinetus is described and illustrated: D. hameri Notton sp.n. from the United Arab Emirates; D. politus stat. rev. is raised in rank to a full species (formerly a subspecies of D. cereolus). Two new subgenera are described: Dentidinetus Olszewski, Notton & Kitching subg.n. and Venustidinetus Olszewski, Notton & Kitching subg.n. and all known species are assigned to subgenera. An illustrated key for identification of world Dinetus species is given and a phylogenetic analysis of Dinetus based on morphological characters is presented.This is an open access article, available to all readers online, published under a creative commons licensing (https://creativecommons.org/licenses/by/4.0/).NHM Repositor
First mitogenome of subfamily Langiinae (Lepidoptera: Sphingidae) with its phylogenetic implications
Get PDFTo date, a relatively complete classification of Sphingidae (Lepidoptera) has been generated, but the phylogeny of the family remains need to be fully resolved. Some phylogenetic relationships within Sphingidae still remains uncertain, especially the taxonomic status of the subfamily Langiinae and its sole included genus and species, Langia zenzeroides. To begin to address this problem, we generated nine new complete mitochondrial genomes, including that of Langia, and together with that of Theretra oldenlandiae from our previous study and 25 other Sphingidae mitogenomes downloaded from GenBank, analyzed the phylogenetic relationships of Sphingidae and investigated the mitogenomic differences among members of the Langiinae, Sphinginae, Smerinthinae and Macroglossinae. The mitogenomes of Sphingidae varied from 14995 bp to 15669 bp in length. The gene order of all newly sequenced mitogenomes was identical, containing 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes and the A + T-rich region. Nucleotide composition was A + T biased, and all the protein-coding genes exhibited a positive AT-skew, which was reflected in the nucleotide composition, codon, and amino acid usage. The A + T-rich region was comprised of nonrepetitive sequences, which contained regulatory elements related to the control of replication and transcription. We analyzed concatenated gene sequences, with third codon positions of protein coding genes and rRNAs excluded, using Maximum Likelihood and Bayesian Inference techniques. All four currently recognized subfamilies were recovered as monophyletic but in contrast to the most recent studies, our preferred tree placed Langiinae as the first subfamily to diverge within Sphingidae rather as sister to Smerinthinae + Sphinginae. Our results also support the removal of the genus Barbourion from the smerinthine tribe Ambulycini to an unresolved position in "Smerinthinae incertae sedis".Copyright © 2021, The Authors. This document is the author’s final accepted version of the journal article. You are advised to consult the published version if you wish to cite from it.NHM Repositor
Evolution of Impatiens (Balsaminaceae) in the Albertine Rift – The endemic Impatiens purpureoviolacea complex consists of ten species
No full textThe Albertine Rift harbours a highly diverse flora with numerous endemic species. An important component of the forestunderstorey is the herbaceous genusImpatiens. Fieldwork in Burundi, the Democratic Republic of the Congo and Rwanda as well asmorphological studies indicated that the Albertine Rift endemicImpatiens purpureoviolacearepresents a species complex. We ana-lyzed the hidden diversity of the complex using morphological and molecular data supplemented by herbarium studies. We found thattheImpatiens purpureoviolaceacomplex can be divided into morphologically and phylogenetically well characterized clades contain-ing ten species and a natural hybrid. We describe all of these species, provide a species key and analyze their evolutionary history.BesideImpatiens purpureoviolaceaandI. gesneroidea, the already describedI. urundiensisis resurrected from synonymy. Two va-rieties,Impatiens purpureoviolaceavar.longicalcarataandI. gesneroideavar.superglabraare raised to species status, and five newspecies (Impatiens elwiraurzulae,I. lotteri,I. ludewigii,I. lutzmannii,I. versicolor) and a new natural hybrid (I. ×troupinii) are de-scribed. Within the mostly insect-pollinated species of the clade, two bird-pollinated species (Impatiens gesneroidea,I. super-glabra) evolved independently. The clade split from its sister taxon in the Pliocene and started diversifying during the Pliocene/Pleistocene transition in parallel to an increased mountain uplifting and volcanic activity in the Albertine Rift. It further diversifiedduring the Pleistocene, likely due to the changes in forest cover and connectivity induced by climatic fluctuations.This is an open access article, available to all readers online, published under a creative commons licensing (https://creativecommons.org/licenses/by/4.0/).NHM Repositor
Review of the Papuan millipede genus Acanthiulus Gervais, 1844 (Diplopoda: Spirobolida: Pachybolidae)
Get PDFThe genus Acanthiulus, which has hitherto been known to comprise three accepted species or subspecies
endemic to the Papuan region, is revised, rediagnosed and shown to include only a single, quite variable species,
A. blainvillei (Leguillou, 1841), with A. blainvillei septemtrionalis Attems, 1914 and A. wollastoni Hirst, 1914 both
considered as its new subjective junior synonyms, syn. nov. Pronounced morphological variations, all clearly
illustrated here, concern only peripheral characters, but the gonopodal structure remains very stable. Three morphs
are distinguished: A, B and C. The distribution of A. blainvillei is mapped, the genus and species apparently being
restricted to the Aru Archipelago, East Indonesia and much of New Guinea, both Indonesian and Papua New Guinea.
Certain clinal variation patterns and an evolutionary scenario can be suggested in the distribution and polymorphism
of the widespread species A. blainvillei at the northern periphery and in the centre of its distribution area.Copyright © 2021, The Entomological Society of Latvia. The attached file is the published version of the article.NHM Repositor
Kleurenkennis
No full textCopyright: Roots Vogelmagazine - permission to deposit granted via email 26/9/22. The attached file is the published version of the article.NHM Repositor