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Morphology of the first instar larva of obligatory traumatic myiasis agents (Diptera: Calliphoridae, Sarcophagidae)
Get PDFThere are only three fly species that are obligate agents of traumatic myiasis of humans and livestock: a single species of flesh fly, Wohlfahrtia magnifica (Sarcophagidae), and two species of blow flies, Chrysomya bezziana and Cochliomyia hominivorax (Calliphoridae). The morphology of their first instar larvae is thoroughly and consistently documented here with light microscopy photographs and scanning electron microscopy micrographs. The following morphological structures are documented: pseudocephalon, antennal complex, maxillary palpus, oral ridges, thoracic and abdominal spinulation, spiracular field, posterior spiracles and cephaloskeleton. New diagnostic features drawn from the cephaloskeleton and the spinulation of abdominal segments, including the anal pad, are discovered and extensively described. Earlier descriptions in the literature are revisited, and major discrepancies between these and the results of the current study are discussed. The present results allow clarification, correction and, especially, complementation of information provided by earlier authors. The relatively distant taxonomic position of all three species is evidence that obligatory myiasis has arisen independently, and the extensively similar morphology in the first instar larvae of Chrysomya bezziana, Cochliomyia hominivorax and W. magnifica in comparison to necrophagous species, especially the enhancement of the anterior part of the cephaloskeleton and the segmental spinulation, is therefore best interpreted as homoplasic adaptations to a life strategy as obligate vertebrate parasites. An identification key for first instar larvae of all obligatory traumatic myiasis agents of mammals is provided.Open Access This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.NHM Repositor
Mining deep-ocean mineral deposits: what are the ecological risks?
Get PDFA key question for the future management of the oceans is whether the mineral deposits that exist on the seafloor of the deep ocean can be extracted without significant adverse effects to the environment. The potential impacts of mining are wide-ranging and will vary depending on the type of metal-rich mineral deposit being mined. There is, currently, a significant lack of information about deep-ocean ecosystems and about potential mining technologies: thus, there could be many unforeseen impacts. Here, we discuss the potential ecological impacts of deep-ocean mining and identify the key knowledge gaps to be addressed. Baseline studies must be undertaken, as well as regular monitoring of a mine area, before, during, and after mineral extraction.The attached document is the author’s submitted version of the journal article. You are advised to consult the publisher’s version if you wish to cite from it.NHM Repositor
A revision of the Maechidiini Burmeister, 1855 (Coleoptera: Scarabaeidae: Melolonthinae) from the Indo-Australian transition zone, and the first record of the tribe west of Wallace’s Line
Get PDFFeatures of the Maechidiini (Scarabaeidae: Melolonthinae) genera Maechidius Macleay, 1819, Epholcis Waterhouse, 1875 and Paramaechidius Frey, 1969 are critically revised and a new synonymy is proposed: Maechidius = Epholcis syn. nov. = Paramaechidius syn. nov. A key to and an annotated checklist of Maechidiini from the Indo-Australian transition zone are presented for the first time. Thirty-five new species are described, namely Maechidius aiyura sp. nov., M. alesbezdeki sp. nov., M. awu sp. nov., M. babyrousa sp. nov., M. bintang sp. nov., M. boessnecki sp. nov., M. brocki sp. nov., M. caperatus sp. nov., M. ciliatus sp. nov., M. crypticus sp. nov., M. dani sp. nov., M. deltouri sp. nov., M. dendrolagus sp. nov., M. hamatus sp. nov., M. kazantsevi sp. nov., M. konjo sp. nov., M. lapsus sp. nov., M. legalovi sp. nov., M. leucopsar sp. nov., M. longipes sp. nov., M. mailu sp. nov., M. maleo sp. nov., M. merdeka sp. nov., M. miklouhomaclayi sp. nov., M. nepenthephilus sp. nov., M. owenstanleyi sp. nov., M. riedeli sp. nov., M. similis sp. nov., M. skalei sp. nov., M. sougb sp. nov., M. suwawa sp. nov., M. trivialis sp. nov., M. ursus sp. nov., M. weigeli sp. nov. and M. yamdena sp. nov. Six new synonyms are proposed: Maechidius Macleay, 1819 = Epholcis Waterhouse, 1875 syn. nov. = Paramaechidius Frey, 1969 syn. nov., Maechidius esau Heller, 1914 = M. setosus Moser, 1920 syn. nov. = M. setosellus Frey, 1969 syn. nov., Maechidius heterosquamosus Heller, 1910 comb. rest. = Paramaechidius clypeatus Frey, 1969 syn. nov. and Maechidius paupianus Heller, 1910 = M. arrowi Frey, 1969 syn. nov. The first records of Maechidiini from the Tanimbar Islands (Yamdena), Sangihe Islands (Sangir) and Lesser Sunda Islands (Bali) are documented, of which the latter two are the northern- and westernmost known records of Maechidius and of the tribe Maechidiini. Lectotypes are designated for 23 species. Fifteen new combinations are proposed and the original combination to Maechidius is restored for four species. Ecological data are presented for the first time for selected Papuan and Wallacean species. Type material of Wallacean and Papuan Maechidiini is depicted for the first time. A key to species is given. In total, 78 species of Maechidiini are confirmed for the Indo-Australian transition zone.Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License (CC BY 4.0) that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.NHM Repositor
Sexual and geographic dimorphism in northern rockhopper penguins breeding in the South Atlantic Ocean
Get PDFThe Endangered northern rockhopper penguin Eudyptes moseleyi, like all penguins, is monomorphic, making sex determination of individuals in the field challenging. We examined the degree of sexual size dimorphism of adult birds across the species’ breeding range in the Atlantic Ocean and developed discriminant functions (DF) to predict individuals’ sex using morphometric measurements. We found significant site-specific differences in both bill length and bill depth, with males being the larger sex on each island. Across all islands, bill length contributed 78% to dissimilarity between sexes. Penguins on Gough Island had significantly longer bills, whilst those from Tristan da Cunha had the deepest. Island-specific DFs correctly classified 82-94% of individuals, and all functions performed significantly better than chance. The model for Nightingale Island correctly classified the greatest proportion of individuals (94-95%), while that for Tristan da Cunha performed the poorest (80-82%). A discriminant function derived from all sites accurately sexed 86-88% of northern rockhopper penguins achieving similar accuracy to island-specific functions. While molecular techniques conclusively determine an individual’s sex, morphometric measurements can provide a reliable estimate with close to 90% accuracy using a method that is less invasive and requires little technical expertise. Sexing is an important tool for meaningful interpretation of ecological data. Consideration of sex-specific differences in future studies will aid investigation of a potential sex-dependent vulnerability in this Endangered species.© The authors 2019. Open Access under Creative Commons by Attribution Licence. Use, distribution and reproduction are unrestricted. Authors and original publication must be credited. The attached file is the published pdf.NHM Repositor
A unique CO-like micrometeorite hosting an exotic Al-Cu-Fe-bearing assemblage – close affinities with the Khatyrka meteorite
Get PDFWe report the discovery of a unique micrometeorite, containing an exotic Al-Cu-Fe alloy composed of two intermixed phases: khatyrkite (CuAl2) and stolperite (CuAl) and both containing minor Fe (<1.4 wt%). These phases are dendritic and rapidly co-crystallized at the binary system’s peritectic (~550 °C). The host micrometeorite is an otherwise typical S-type micro-porphyritic cosmic spherule containing relict olivine (Fo76–90, Cr2O3: 0.01–0.56 wt%, MnO: 0.03–0.32 wt% and CaO: 0.09–0.22 wt%) and a cumulate layered texture. These properties suggest the micrometeorite is derived from a carbonaceous chondrite (best matched to a CO chondrite) and entered the atmosphere a high speed (~16 kms−1), implying an origin from a highly eccentric orbit. This particle represents the second independent discovery of naturally occurring intermetallic Al-Cu-Fe alloys and is thus similar to the previously reported Khatyrka meteorite - a CV chondrite containing near-identical alloys and the only known natural quasicrystals. We did not observe quasicrystalline phases in this micrometeorite, likely due to the low amounts of Fe in the alloy, insufficient to stabilize quasicrystals. Our discovery confirms the existence of Al-Cu-Fe intermetallic alloys on chondritic parent bodies. These unusual phases require a currently unexplained formation process, we tentatively suggest this could represent the delivery of exotic interstellar material to the inner solar system via impact.© The Author(s) 2019. 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. Te 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/.NHM Repositor
Reproductive phenotype predicts adult bite-force performance in sex-reversed dragons (Pogona vitticeps )
Get PDFSex‐related differences in morphology and behavior are well documented, but the relative contributions of genes and environment to these traits are less well understood. Species that undergo sex reversal, such as the central bearded dragon (Pogona vitticeps), offer an opportunity to better understand sexually dimorphic traits because sexual phenotypes can exist on different chromosomal backgrounds. Reproductively female dragons with a discordant sex chromosome complement (sex reversed), at least as juveniles, exhibit traits in common with males (e.g., longer tails and greater boldness). However, the impact of sex reversal on sexually dimorphic traits in adult dragons is unknown. Here, we investigate the effect of sex reversal on bite‐force performance, which may be important in resource acquisition (e.g., mates and/or food). We measured body size, head size, and bite force of the three sexual phenotypes in a colony of captive animals. Among adults, we found that males (ZZm) bite more forcefully than either chromosomally concordant females (ZWf) or sex‐reversed females (ZZf), and this difference is associated with having relatively larger head dimensions. Therefore, adult sex‐reversed females, despite apparently exhibiting male traits as juveniles, do not develop the larger head and enhanced bite force of adult male bearded dragons. This pattern is further illustrated in the full sample by a lack of positive allometry of bite force in sex‐reversed females that is observed in males. The results reveal a close association between reproductive phenotype and bite force performance, regardless of sex chromosome complement.This is the peer reviewed version of the following article: Jones, MEH, Pistevos, JCA, Cooper, N, et al. Reproductive phenotype predicts adult bite‐force performance in sex‐reversed dragons (Pogona vitticeps). J Exp Zool. 2020; 1– 12. https://doi.org/10.1002/jez.2353, which has been published in final form at https://doi.org/10.1002/jez.2353. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. The attached file is the final accepted manuscript version, you are advised to consult the publisher’s version if you wish to cite from it.NHM Repositor
How metalliferous brines line Mexican epithermal veins with silver
Get PDFWe determined the composition of ~30-m.y.-old solutions extracted from fluid inclusions in one of the world's largest and richest silver ore deposits at Fresnillo, Mexico. Silver concentrations average 14 ppm and have a maximum of 27 ppm. The highest silver, lead and zinc concentrations correlate with salinity, consistent with transport by chloro-complexes and confirming the importance of brines in ore formation. The temporal distribution of these fluids within the veins suggests mineralization occurred episodically when they were injected into a fracture system dominated by low salinity, metal-poor fluids. Mass balance shows that a modest volume of brine, most likely of magmatic origin, is sufficient to supply the metal found in large Mexican silver deposits. The results suggest that ancient epithermal ore-forming events may involve fluid packets not captured in modern geothermal sampling and that giant ore deposits can form rapidly from small volumes of metal-rich fluid.This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-nd/3.0/. The attached file is the published pdf.NHM Repositor
North Africa's first stegosaur: Implications for Gondwanan thyreophoran dinosaur diversity
Get PDFEurypoda, the major radiation of armoured dinosaurs, comprises the ankylosaurs and their sister group, the stegosaurs. As the earliest-branching major clade of ornithischian dinosaurs, the evolutionary history of Eurypoda is significant for understanding both the palaeobiology of bird-hipped dinosaurs and the composition of middle Mesozoic ecosystems. Eurypodans were diverse and abundant throughout the Late Jurassic and Cretaceous in Laurasia; in contrast, their remains are extremely rare in Gondwana. Herein, we describe a new genus and species of stegosaur from the Middle Jurassic of Morocco, Adratiklit boulahfa. Adratiklit is the first eurypodan from north Africa and the oldest definitive stegosaur from anywhere in the world. The genus is more closely related to the European stegosaurs Dacentrurus and Miragaia than it is to the southern African taxa Kentrosaurus and Paranthodon. Statistically significant correlations between the number of dinosaur-bearing formations, dinosaur-bearing collections, and eurypodan occurrences in Gondwana indicates that their fossil record is biased by both geological and anthropogenic factors. Tantalizing but fragmentary remains and trackways suggest that eurypodan diversity in Gondwana may have been as rich as that of Laurasia, and the prospects for future discoveries of new genera across Gondwana are therefore very good.‘The attached document is the authors’ final accepted/submitted version of the journal article. You are advised to consult the publisher’s version if you wish to cite from it.NHM Repositor
Evaluation of DNA barcode libraries used in the UK and developing an action plan to fill priority gaps
Get PDFThere are approximately 76,000 eukaryote species recognised in the UK, and while we know some of them in great detail, the majority of these species are poorly known, and hundreds of new species are discovered each year. DNA barcoding uses a short, standardised segment of an organism’s genome for identification by comparison to a reference library; however, the UK lags behind several countries in Europe and North America in that we lack trusted, reliable and openly accessible reference sequences for key UK taxa. This report is the first step in rectifying this by engaging diverse stakeholders to facilitate collaboration and coordination; providing robust stakeholder-based and independent assessment of the current state of reference libraries available for all known UK taxa; and prioritising key taxa. A survey was developed and shared with the UK research and end user community, receiving 80 responses from a wide range of stakeholders and covering the focal taxa / assemblages and habitats; the DNA reference libraries in use, their quality assurance and perceived coverage. A formal gap analysis of the public DNA data in major DNA reference libraries highlighted that an estimated 52% of UK species have publicly available DNA data of some sort; however, coverage in gene specific reference libraries varies greatly (eg 2 – 52%), as does the associated quality assurance. Priority taxa highlighted by end users had coverage in reference libraries ranging from almost complete, in the case of known invasive non-native species, to significant coverage (71%) for taxa with conservation designations. However, these data also vary by kingdom and reference library, as does the associated quality assurance. If taking a strict requirement of DNA data provided by UK specimens and held in UK repositories, for robust QC and QA, then the proportion of UK species with public DNA data in reference libraries falls to less than 4% in the largest reference library assessed (BOLD). While standard genes for DNA-based identification have essentially been established, more work is required to establish the priority taxa required for regulatory delivery in contrast to taxa that are surveyed in a non-regulatory framework. Several barriers to the development of barcode libraries were highlighted, the most relevant being sustained large scale funding, expertise, capacity, laboratory skills and equipment, quality control and assurance, collecting logistics (eg permits and access) and communication. Significant opportunities identified include a large network of interested experts, several organisations with significant delivery capabilities, current large-scale projects and funding opportunities, emerging technologies and the economy of scale for DNA sequencing. Following a stakeholder workshop, we have outlined a concise action plan to provide reliable, open access reference sequences, linked to open access vouchers, identified by known experts, to facilitate UK academic and regulatory aims.This report is published by Natural England under the Open Government Licence - OGLv3.0 for public sector
information. You are encouraged to use, and reuse, information subject to certain conditions. For details of the
licence visit Copyright. Natural England photographs are only available for non-commercial purposes. If any other
information such as maps or data cannot be used commercially this will be made clear within the report.
ISBN 978-1-78354-671-8
© Natural England and other parties 2020
© Trustees of the Natural History Museum, LondonNHM Repositor
Rediscovery of the syntypes of California Quail Tetrao californicus Shaw, 1798, and comments on the current labelling of the holotype of California Condor Vultur californianus Shaw, 1797
Get PDFThe two syntypes of California Quail Tetrao californicus Shaw, 1798,
were deposited in the British Museum in the 1790s, but were last documented as
present in the late 1860s and had subsequently been presumed no longer extant.
In 2004, they were re-discovered in Notingham Natural History Museum, to
which they must have been inadvertently passed as ‘duplicates’ in the late 1800s,
and have now been returned to the Natural History Museum, Tring, on extended
renewable loan. During research regarding these Archibald Menzies specimens,
new insight was gained into hitherto confusing reference details on the label of his
type specimen of California Condor Vultur californianus Shaw, 1797© 2014 The Authors; Journal compilation © 2014 British Ornithologists’ Club. This is an open access article free to all. The attached file is the published pdf.NHM Repositor