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Bones and genes: resolution problems in three Vietnamese species of Crocidura (Mammalia, Soricomorpha, Soricidae) and the description of an additional new species
Get PDFTimes Cited: 0 0 Import from WoS only - CL not assigned grouping, NHM authors etc.Recent investigations of Southeast Asian white toothed shrews belonging to the genus Crocidura have revealed discrepancies between the results of morphological and molecular studies. The following study concerns three species of Crocidura occurring in Vietnam, namely Crocidura attenuata, Crocidura tanakae and Crocidura wuchihensis, and an undescribed fourth species revealed by molecular analysis. For many years Crocidura attenuata has been known to occur in Vietnam but, until very recently, the morphologically similar and comparably sized Crocidura tanakae was believed to be restricted to Taiwan. Following several molecular studies over the last few years, this species is now believed to be considerably more widespread and recognised as occuring also in Vietnam. The results of one of these recent molecular studies also revealed the presence of an undescribed species of Crocidura, similar in size and morphology to Crocidura wuchihensis, which is herein described. Data are provided on geographical variation in Vietnam and the problems of defining morphologically similar yet molecularly disparate species are discussed.Copyright Paulina D. Jenkins et al. This is an open access article distributed under the terms of the Creative Commons Attribution License 3.0 (CC-BY), 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
The genus Orionis Shaw (Hymenoptera, Braconidae, Euphorinae) in the Old World
No full textThe euphorine braconid genus Orionis Shaw, 1987 is found to be more diverse in the Old World than had previously been recognised. Orionis was regarded previously as largely Neotropical, with one Oriental species (Orionis orientalis Shimbori & Shaw, 2016) known from Thailand, but we recognise an additional three species from the Oriental and Palaearctic regions. Three species of Euphorinae are transferred to Orionis Shaw, 1987 and are new combinations: Orionis coxator (Belokobylskij, 1995), comb. nov., Orionis erratus (Chen & van Achterberg, 1997), comb. nov., and Orionis flavifacies (Belokobylskij, 2000), comb. nov. Previously known from the Far Eastern Palaearctic, O. coxator has surprisingly been found in Europe, in Belgium, England and the Netherlands. The inclusion of these species in Orionis whereas most previous species have been described from the Neotropics, is justified by Bayesian analysis of the D2 region of 28S, Cytochrome Oxidase I barcode sequences, and morphology.Copyright Gavin R. Broad, Julia Stigenberg. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are creditedNHM Repositor
Miniaturization in Direct-Developing Frogs from Mexico with the Description of Six New Species
Get PDFThe Craugastor mexicanus series (Anura: Craugastoridae) includes six species of direct-developing frogs that occur in Mexico and Guatemala. Notably, two of these species have small adult body sizes (<18 mm snout to vent length) and several have intraspecific polymorphism in color pattern. Using a geographic sampling focused on eastern Mexico (the location of most type localities), we conducted a molecular phylogenetic analysis of two mitochondrial (12S, 16S) and two nuclear (RAG1, TYR) gene fragments. This analysis revealed two widespread species, C. mexicanus and C. pygmaeus, along with evidence of multiple undescribed taxa from the states of Oaxaca, Mexico, Guerrero, and Jalisco. Interestingly, the widespread species have stratified geographic distributions with the larger bodied clade restricted to high elevations and the smaller bodied clade to low elevations. We also identify regions of Guerrero and Oaxaca where multiple species co-occur. To reevaluate the quality of characters that have been previously used to diagnose species, we tested for heterochrony and sexual dimorphism using microcomputed tomography and linear measurements. We found evidence for paedomorphosis as the mechanism of miniaturization in small-bodied taxa. Linear measurements confirmed that tympanum and body size are sexually dimorphic traits in both small- and large-bodied species. We used this enhanced understanding of morphological variation in the group to describe six new species. Despite this progress, we suspect that additional species await discovery, particularly in western Mexico and east of the Isthmus of Tehuantepec where our sampling efforts were limited.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
A standardised method for estimating the level of visible debris in bird nests
Get PDFUnlike records of plastic ingestion and entanglement in seabirds which date back to the 1960s, the literature regarding debris in bird nests is comparatively limited. It is important to identify standardised methods early so that data are collected in a consistent manner, ensuring that future studies can be comparable. Here, we outline a method that can be applied to photographs for estimating the proportion of visible debris at the surface of a nest. This method uses ImageJ software to superimpose a grid onto a photograph of a nest/s. The number of cells with and without debris are then counted. Our proposed method is repeatable, straightforward, and accessible. We optimised the method to estimate the level of visible debris in Northern Gannet (Morus bassanus) nests, however, with some modification (i.e., adjustment of grid cell size), it could be applied to other seabird species, and terrestrial birds, that incorporate debris within nests.The attached document is the authors’ final accepted version of the journal article. You are advised to consult the publisher’s version if you wish to cite from it.NHM Repositor
The two extinctions of the Carolina Parakeet Conuropsis carolinensis
No full textDue to climate change and habitat conversion, estimates of the resulting levels of species extinction over the next century are alarming. Devising conservation solutions will require many different approaches, including examining the extinction processes of recently extinct species. Given that parrots are one of the most threatened groups of birds, information regarding parrot extinction is pressing. While most recent parrot extinctions have been island endemics, the Carolina Parakeet Conuropsis carolinensis had an 18th-century range covering nearly half of the present-day United States, yet mostly disappeared by the end of the 19th century. Despite a great deal of speculation, the major cause of its extinction remains unknown. Establishing the date when a species went extinct is one of the first steps in determining what caused their extinction. While there have been estimates of their extinction date, these analyses used a limited dataset and did not include observational data. We used a recently published, extensive dataset of Carolina Parakeet specimens and observations combined with a Bayesian extinction estimating model to determine the most likely extinction dates. By considering each of the two subspecies independently, we found that they went extinct ˜30 years apart: the western subspecies C. c. ludovicianus going extinct around 1914 and the eastern subspecies C. c. carolinensis either in the late 1930s or mid-1940s. Had we only considered all observations together, this pattern would have been obscured, possibly missing a major clue in solving the mystery of the parakeet’s extinction. Since the Carolina Parakeet was a wide-ranging species that went extinct during a period of rapid agricultural and industrial expansion, conditions that mirror those occurring in many parts of the world where parrot diversity is highest, any progress we make in unraveling the mystery of their disappearance may be vital to modern conservation efforts.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
Development of a recombinase polymerase amplification (RPA) fluorescence assay for the detection of Schistosoma haematobium
Get PDFAbstract
Background
Accurate diagnosis of urogenital schistosomiasis is vital for surveillance and control programmes. While a number of diagnostic techniques are available there is a need for simple, rapid and highly sensitive point-of-need (PON) tests in areas where infection prevalence and intensity are low. Recombinase Polymerase Amplification (RPA) is a sensitive isothermal molecular diagnostic technology that is rapid, portable and has been used at the PON for several pathogens.
Results
A real time fluorescence RPA assay (RT-ShDra1-RPA) targeting the Schistosoma haematobium Dra1 genomic repeat region was developed and was able to detect 1 fg of S. haematobium gDNA. Results were obtained within 10 minutes using a small portable battery powered tube scanner device that incubated reactions at 40 °C, whilst detecting DNA amplification and fluorescence over time. The assay’s performance was evaluated using 20 urine samples, with varying S. haematobium egg counts, from school children from Pemba Island, Zanzibar Archipelago, Tanzania. Prior to RPA analysis, samples were prepared using a quick crude field DNA extraction method, the Speed Extract Kit (Qiagen, Manchester, UK). Positive assay results were obtained from urine samples with egg counts of 1–926 eggs/10 ml, except for two samples, which had inconclusive results. These two samples had egg counts of two and three eggs/10 ml of urine.
Conclusions
The RT-ShDra1-RPA assay proved robust for S. haematobium gDNA detection and was able to amplify and detect S. haematobium DNA in urine samples from infected patients. The assay’s speed and portability, together with the use of crude sample preparation methods, could advance the rapid molecular diagnosis of urogenital schistosomiasis at the PON within endemic countries.Copyright © The Author(s) 2019. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided 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 Creative Commons Public Domain Dedication waiver (http://creativecommons.org/ publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. The attached file is the published version of the article.NHM Repositor
Bidirectional Introgressive Hybridization between a Cattle and Human Schistosome Species
Get PDFSchistosomiasis is a disease of great medical and veterinary importance in tropical and subtropical regions, caused by parasitic flatworms of the genus Schistosoma (subclass Digenea). Following major water development schemes in the 1980s, schistosomiasis has become an important parasitic disease of children living in the Senegal River Basin (SRB). During molecular parasitological surveys, nuclear and mitochondrial markers revealed unexpected natural interactions between a bovine and human Schistosoma species: S. bovis and S. haematobium, respectively. Hybrid schistosomes recovered from the urine and faeces of children and the intermediate snail hosts of both parental species, Bulinus truncatus and B. globosus, presented a nuclear ITS rRNA sequence identical to S. haematobium, while the partial mitochondrial cox1 sequence was identified as S. bovis. Molecular data suggest that the hybrids are not 1st generation and are a result of parental and/or hybrid backcrosses, indicating a stable hybrid zone. Larval stages with the reverse genetic profile were also found and are suggested to be F1 progeny. The data provide indisputable evidence for the occurrence of bidirectional introgressive hybridization between a bovine and a human Schistosoma species. Hybrid species have been found infecting B. truncatus, a snail species that is now very abundant throughout the SRB. The recent increase in urinary schistosomiasis in the villages along the SRB could therefore be a direct effect of the increased transmission through B. truncatus. Hybridization between schistosomes under laboratory conditions has been shown to result in heterosis (higher fecundity, faster maturation time, wider intermediate host spectrum), having important implications on disease prevalence, pathology and treatment. If this new hybrid exhibits the same hybrid vigour, it could develop into an emerging pathogen, necessitating further control strategies in zones where both parental species overlap.Copyright © 2009 Huyse 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 attached file is the published version of the article.NHM Repositor
Erratum to: Development of novel multiplex microsatellite polymerase chain reactions to enable high-throughput population genetic studies of Schistosoma haematobium
Get PDFUnfortunately, the original version of this article [1], contained a mistake. In Table 1, the primers for Sh6 and Sh9 were included incorrectly. Instead of GGGATGTATGCAGACTTG TTGTTTGGCTGCAGTAAC and GCTGAGCTTGAGATTG CTTCTGTCCCATCGATACC they should have been Sh6 Forward Primer GGTGGATTACGCAATAG, Sh6 Reverse Primer TTTAATCAACCGGGTGTC and Sh9 Forward Primer GGGATGTATGCAGACTTG, Sh9 Reverse Primer TTGTTTGGCTGCAGTAAC respectively. A corrected version of Table 1 is included belowCopyright: © 2015 Webster et al. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided 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 Creative Commons Public Domain Dedication waiver (http://creativecommons.org/ publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. The attached file is the published version of the article.NHM Repositor
Intestinal Schistosomiasis and Giardiasis Co-Infection in Sub-Saharan Africa: Can a One Health Approach Improve Control of Each Waterborne Parasite Simultaneously?
Get PDFBoth intestinal schistosomiasis and giardiasis are co-endemic throughout many areas of sub-Saharan Africa, significantly impacting the health of millions of children in endemic areas. While giardiasis is not considered a neglected tropical disease (NTD), intestinal schistosomiasis is formally grouped under the NTD umbrella and receives significant advocacy and financial support for large-scale control. Although there are differences in the epidemiology between these two diseases, there are also key similarities that might be exploited within potential integrated control strategies permitting tandem interventions. In this review, we highlight these similarities and discuss opportunities for integrated control of giardiasis in low and middle-income countries where intestinal schistosomiasis is co-endemic. By applying new, advanced methods of disease surveillance, and by improving the provision of water, sanitation and hygiene (WASH) initiatives, (co)infection with intestinal schistosomiasis and/or giardiasis could not only be more effectively controlled but also better understood. In this light, we appraise the suitability of a One Health approach targeting both intestinal schistosomiasis and giardiasis, for if adopted more broadly, transmission of both diseases could be reduced to gain improvements in health and wellbeing.Copyright: ©2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). The attached file is the published version of the article.NHM Repositor
Cryptic population decrease due to invasive species predation in a long‐lived seabird supports need for eradication
Get PDFSUMMARY
1. Invasive species are one of the greatest drivers of biodiversity loss worldwide, but the eradication of invasive species from islands is a highly efficient management strategy. Because eradication operations require large financial investments, uncertainty over the magnitude of impacts of both invasive species and their removal can impede the willingness of decision makers to invest in eradication. Such uncertainty is prevalent for long-lived species that display an inherent lag between life stages affected by invasive species and those used for population status assessments.
2. Albatrosses are among the longest-living bird species and are threatened on land by invasive species and at sea by industrial fisheries. As in many seabird species, usually only a segment of the population (breeding adults) is used for status assessments, making it difficult to assess their population trends and the potential benefit of conservation action, such as the management of predatory invasive species.
3. We used population monitoring and mark-recapture data to estimate the past population trajectory of the Critically Endangered Tristan Albatross (Diomedea dabbenena) by accounting for unobservable birds at sea in an integrated population model. We then projected the future population trajectory for scenarios with or without predation by invasive house mice (Mus musculus) on their main site, Gough Island.
4. The adult breeding population remained stable between 2004 and 2021, but breeding success was low (31%) and our model indicated that the total population (including unobservable immature birds) decreased from a median estimate of 9795 to 7752 birds. Eradicating invasive mice leading to a two-fold increase in breeding success would result in a 1.8–7.6 times higher albatross population by 2050 (median estimate 10 352 individuals) than without this intervention.
5. Low reproductive output for long-lived species may lead to a cryptic population decrease, which can be obscured from readily available counts of breeding pairs by changes in the breeding population. Mouse eradication is necessary to revert the ongoing population decrease, even if this decrease is not yet apparent in the breeding population size.Copyright: © 2022 The Authors. This document is the author’s submitted version of the journal article. You are advised to consult the published version if you wish to cite from it.NHM Repositor