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1.
Mol Ecol Resour ; 24(3): e13925, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38183389

ABSTRACT

Sequence data assembly is a foundational step in high-throughput sequencing, with untold consequences for downstream analyses. Despite this, few studies have interrogated the many methods for assembling phylogenomic UCE data for their comparative efficacy, or for how outputs may be impacted. We study this by comparing the most commonly used assembly methods for UCEs in the under-studied bee lineage Nomiinae and a representative sampling of relatives. Data for 63 UCE-only and 75 mixed taxa were assembled with five methods, including ABySS, HybPiper, SPAdes, Trinity and Velvet, and then benchmarked for their relative performance in terms of locus capture parameters and phylogenetic reconstruction. Unexpectedly, Trinity and Velvet trailed the other methods in terms of locus capture and DNA matrix density, whereas SPAdes performed favourably in most assessed metrics. In comparison with SPAdes, the guided-assembly approach HybPiper generally recovered the highest quality loci but in lower numbers. Based on our results, we formally move Clavinomia to Dieunomiini and render Epinomia once more a subgenus of Dieunomia. We strongly advise that future studies more closely examine the influence of assembly approach on their results, or, minimally, use better-performing assembly methods such as SPAdes or HybPiper. In this way, we can move forward with phylogenomic studies in a more standardized, comparable manner.


Subject(s)
Phylogeny , Bees/genetics , Animals
2.
Data Brief ; 48: 109181, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37180879

ABSTRACT

A dataset describing the occurrence of wild bees and their interaction with forage plants along livestock grazing gradient is critical in understanding bee-plant interaction networks and in developing conservation plans to ensure ecosystem services in human-modified landscapes. Despite this need, bee-plant datasets are scarce in Africa, and Tanzania is no exception. Therefore, in this article, we present a dataset of wild bee species richness, occurrence, and distribution collected across sites with different levels of livestock grazing intensity and forage resources thereby. The data presented in this paper supports a research article by Lasway et al., 2022 describing the effects of grazing intensity on East African bee assemblages. The paper presents primary data on bee species, collection method, date of collection, bee family, identifier, plant forage resource, forage plant life form, forage plant family, location (GPS coordinates), grazing intensity category, mean annual temperature (°C), and elevation (m asl). The data were collected intermittently between August 2018 and March 2020 from 24 study sites distributed along three levels of livestock grazing intensity with eight replicates for each: low, moderate, and high livestock grazing intensity. In each study site, two 50 × 50 m study plots were set from which bees and floral resources were sampled and quantified. The two plots were placed in a way to capture the overall structural heterogeneity of the respective habitat by placing the two plots in contrasting microhabitats where possible. For example, in moderately livestock-grazed habitats, plots were placed on sites with and without tree or shrub cover to ensure representativeness. This paper presents a dataset comprising 2,691 bee individuals from 183 species representing 55 genera of the five bee families: Halictidae (74), Apidae (63), Megachilidae (40), Andrenidae (5), and Colletidae (1). In addition, the dataset comprises 112 species of flowering plants that were identified as potential forage resources for bees. This paper supplements rare but critical data on bee pollinators in Northern Tanzania and advances our knowledge of the potential drivers of bee-pollinator whose populations diversity are declining globally. The dataset will also promote collaborations among researchers who would wish to combine and extend their data for further analysis to gain a broader understanding of the phenomenon on a larger spatial scale.

3.
Zootaxa ; 5263(1): 107-121, 2023 Apr 04.
Article in English | MEDLINE | ID: mdl-37044996

ABSTRACT

Two new species are described in the genus Pseudapis: P. kuhlmanni Pauly & Monks, and P. lisetae Pauly & Monks, both from Oman. Their distributional and flower-visiting data are presented, and they are diagnosed and differentiated from other species in the genus.


Subject(s)
Hymenoptera , Bees , Animals , Oman , Animal Distribution
4.
J Anim Ecol ; 92(5): 1001-1015, 2023 05.
Article in English | MEDLINE | ID: mdl-36754546

ABSTRACT

We studied α- and ß-diversity of pollinators, flowering plants and plant-pollinator interactions along the altitudinal gradient of Mt. Olympus, a legendary mountain and biodiversity hotspot in Central Greece. We explored 10 study sites located on the north-eastern slope of the mountain, from 327 to 2596 m a.s.l. Insect surveys were conducted once a month using hand netting (years 2013, 2014 and 2016), and they were combined with recordings of flowering plant diversity (species richness and flower cover). We then calculated α- and ß-diversity of pollinators, plants in flower and plant-pollinator interactions, and explored their demographic response along the altitudinal gradient. Alpha diversity of pollinators, plants and plant-pollinator interactions were altitude dependent; α-diversity of all pollinators, bees, non-bumblebee bees, bee flies and butterflies showed linear declines with altitude, whereas those of hoverflies and bumblebees showed unimodal patterns. Beta diversity and its turnover component of all pollinators, hoverflies, bees, bumblebees, non-bumblebee bees, butterflies and plants showed linear increases, whereas those of bee flies and of plant-pollinator interactions varied independently from the pairwise altitudinal difference. The high dissimilarity and uniqueness of pollination networks, which is probably a result of the high biodiversity and endemism of Mt. Olympus, is driven by species turnover and the formation of new interactions between new species. Contrasting to the monotonic decline of the remaining groups, the unimodal patterns of hoverfly and bumblebee α-diversity are probably the effect of a higher tolerance of these groups to high-altitude environmental conditions. Our findings highlight that the high turnover of species and of pollination interactions along the altitudinal gradient are the mainstay of hyperdiverse mountains, a fact that conveys important historical, ecological and conservational implications.


Subject(s)
Butterflies , Diptera , Magnoliopsida , Bees , Animals , Insecta/physiology , Pollination/physiology , Biodiversity , Flowers/physiology , Plants
5.
Zootaxa ; 5392(1): 1-103, 2023 Dec 27.
Article in English | MEDLINE | ID: mdl-38220995

ABSTRACT

Natural history collections are a cornerstone of entomology, and the conservation of specimens is the essential prerequisite for the development of research into systematics, biogeography, ecology, evolution and other disciplines. Yet, specimens collected during decades of entomological research conducted in less developed countries across Sub-Saharan Africa on pests, beneficial insects and insect biodiversity in general have largely been exported to be permanently preserved in developed countries, mainly in Europe and the United States of America. This is particularly true for the Democratic Republic of the Congos (DRC) diverse wild bee fauna, which has been investigated throughout the colonial period by visiting or resident entomologists and missionaries who have then transferred their collected material primarily to Belgium as part of a wider legacy of scientific exploration and colonialism. Digitizing NHC is one way to mitigate this current bias, by making samples accessible to researchers from the target post-colonial countries as well as to the wider international scientific community. In this study, we compiled and digitized 6,490 specimens records relevant to 195 wild bee species grouped in 18 genera within the biodiverse family Megachilidae, essentially from the colonial era (i.e., mostly between 19051960, with additional records up to 1978), and curated at the Royal Museum for Central Africa in Belgium. We provide a detailed catalogue of all records with updated locality and province names, including 29 species only available as type specimens. We also explore the historical patterns of diversity and distribution across DRC, and we provide a list of the research entomologists involved. This study is an important first step that uses digital technologies to democratize and repatriate important aspects of DRCs natural heritage of insect biodiversity, to stimulate more contemporary field surveys and modern taxonomic revisions, as well as to identify and characterize research gaps and biodiversity shortfalls in some of the less-explored regions of Sub-Saharan Africa.


Subject(s)
Hymenoptera , Bees , Animals , Belgium , Democratic Republic of the Congo , Museums , Africa, Central , Insecta
6.
Zookeys ; 1090: 103-111, 2022.
Article in English | MEDLINE | ID: mdl-35586843

ABSTRACT

Two Chinese species of the genus Lipotriches Gerstaecker, 1858 are treated in this paper. Lipotriches (Lipotriches) guihongi Zhang & Niu, sp. nov. is recognized as a new species and Lipotriches (Maynenomia) nanensis (Cockerell, 1929) is a new species and subgenus record for China. The number of Chinese species of the subfamily Nomiinae and genus Lipotriches are updated to 47 and 15, respectively.

7.
Polymers (Basel) ; 14(5)2022 Feb 24.
Article in English | MEDLINE | ID: mdl-35267714

ABSTRACT

We combined a conducting polymer, polyaniline (PANI), with an organic semiconducting macrocyclic (MCs) material. The macrocycles are the phthalocyanines and porphyrins used to tune the electrical properties of the PANI, which benefits from their ability to enhance sensor response. For this, we proceeded by a simple ultrasonically assisted reaction involving the two components, i.e., the PANI matrix and the MCs, to achieve the synthesis of the composite nanostructure PANI/MCs. The composite nanostructure has been characterized and deposited on interdigitated electrodes (IDEs) to construct resistive sensor devices. The isolated nanostructured composites present good electrical properties dominated by PANI electronic conductivity, and the characterization reveals that both components are present in the nanostructure. The experimental results obtained under gas exposures show that the composite nanostructures can be used as a sensing material with enhanced sensing properties. The sensing performance under different conditions, such as ambient humidity, and the sensor's operating temperature are also investigated. Sensing behavior in deficient humidity levels and their response at different temperatures revealed unusual behaviors that help to understand the sensing mechanism. Gas sensors based on PANI/MCs demonstrate significant stability over time, but this stability is highly reduced after experiments in lower humidity conditions and at high temperatures.

8.
Biodivers Data J ; 9: e68190, 2021.
Article in English | MEDLINE | ID: mdl-34497474

ABSTRACT

BACKGROUND: Bees (Hymenoptera: Apoidea: Anthophila) are the most important group of pollinators with about 20,507 known species worldwide. Despite the critical role of bees in providing pollination services, studies aiming at understanding which species are present across disturbance gradients are scarce. Limited taxononomic information for the existing and unidentified bee species in Tanzania make their conservation haphazard. Here, we present a dataset of bee species records obtained from a survey in nothern Tanzania i.e. Kilimanjaro, Arusha and Manyara regions. Our findings serve as baseline data necessary for understanding the diversity and distribution of bees in the northern parts of the country, which is a critical step in devising robust conservation and monitoring strategies for their populations. NEW INFORMATION: In this paper, we present information on 45 bee species belonging to 20 genera and four families sampled using a combination of sweep-netting and pan trap methods. Most species (27, ~ 60%) belong to the family Halictidae followed by 16 species (35.5%) from the family Apidae. Megachilidae and Andrenidae were the least represented, each with only one species (2.2%). Additional species of Apidae and Megachilidae sampled during this survey are not yet published on Global Biodiversity Information Facility (GBIF), once they will be available on GBIF, they will be published in a subsequent paper. From a total of 953 occurrences, highest numbers were recorded in Kilimanjaro Region (n = 511), followed by Arusha (n = 410) and Manyara (n = 32), but this pattern reflects the sampling efforts of the research project rather than real bias in the distributions of bee species in northern Tanzania.

9.
Zootaxa ; 4976(1): 1146, 2021 May 27.
Article in English | MEDLINE | ID: mdl-34187022

ABSTRACT

The study of wild bees has markedly increased in recent years due to their importance as pollinators of crops and wild plants, and this interest has been accentuated by increasing evidence of global declines in their abundance and species richness. Though best studied in Europe and North America, knowledge on the current state of wild bees is scarce in regions where they are particularly diversified, such as the Mediterranean basin. The eastern Mediterranean country of Lebanon, located at the heart of the Levant in a biodiversity hotspot, is particularly poorly studied. The aim of this paper is to produce a first annotated checklist of the wild bees of Lebanon from new and museum collections, literature records, and verified occurrences from online databases. The present list totals 573 species for Lebanon of which 289 are reported for the first time, but the estimated diversity is likely to be closer to 700. Preliminary information on local distributions and flower records are also presented. The local species assemblages indicate affinities with montane habitats of the Mediterranean and Anatolia and the semi-arid habitats of the Levant and north Africa. This study also encourages further research on local wild bee faunas and the use of this knowledge for conservation purposes.


Subject(s)
Bees/classification , Animal Distribution , Animals , Flowers , Lebanon , Pollination
10.
Syst Biol ; 70(4): 803-821, 2021 06 16.
Article in English | MEDLINE | ID: mdl-33367855

ABSTRACT

Summarizing individual gene trees to species phylogenies using two-step coalescent methods is now a standard strategy in the field of phylogenomics. However, practical implementations of summary methods suffer from gene tree estimation error, which is caused by various biological and analytical factors. Greatly understudied is the choice of gene tree inference method and downstream effects on species tree estimation for empirical data sets. To better understand the impact of this method choice on gene and species tree accuracy, we compare gene trees estimated through four widely used programs under different model-selection criteria: PhyloBayes, MrBayes, IQ-Tree, and RAxML. We study their performance in the phylogenomic framework of $>$800 ultraconserved elements from the bee subfamily Nomiinae (Halictidae). Our taxon sampling focuses on the genus Pseudapis, a distinct lineage with diverse morphological features, but contentious morphology-based taxonomic classifications and no molecular phylogenetic guidance. We approximate topological accuracy of gene trees by assessing their ability to recover two uncontroversial, monophyletic groups, and compare branch lengths of individual trees using the stemminess metric (the relative length of internal branches). We further examine different strategies of removing uninformative loci and the collapsing of weakly supported nodes into polytomies. We then summarize gene trees with ASTRAL and compare resulting species phylogenies, including comparisons to concatenation-based estimates. Gene trees obtained with the reversible jump model search in MrBayes were most concordant on average and all Bayesian methods yielded gene trees with better stemminess values. The only gene tree estimation approach whose ASTRAL summary trees consistently produced the most likely correct topology, however, was IQ-Tree with automated model designation (ModelFinder program). We discuss these findings and provide practical advice on gene tree estimation for summary methods. Lastly, we establish the first phylogeny-informed classification for Pseudapis s. l. and map the distribution of distinct morphological features of the group. [ASTRAL; Bees; concordance; gene tree estimation error; IQ-Tree; MrBayes, Nomiinae; PhyloBayes; RAxML; phylogenomics; stemminess].


Subject(s)
Models, Genetic , Animals , Bayes Theorem , Bees/genetics , Phylogeny
11.
Zootaxa ; 4892(1): zootaxa.4892.1.1, 2020 Dec 07.
Article in English | MEDLINE | ID: mdl-33311101

ABSTRACT

Morocco is a well known hot-spot of biodiversity in the Mediterranean basin. While some taxa like vascular plants are relatively well recorded, important groups of pollinators like bees are still understudied. This article presents an updated checklist of the bee species of Morocco and includes a summary of global and regional distribution of each species. A total of 961 species belonging to six bee families and 68 genera are recorded: Andrenidae (8 genera, 217 species); Apidae (15 genera, 241 species); Colletidae (2 genera, 74 species), Halictidae (12 genera, 144 species), Megachilidae (28 genera, 271 species) and Melittidae (3 genera, 14 species). Among them, 67 species are recorded for the first time in Morocco. Around 70% of the bee fauna of Morocco consists of widespread Palaearctic species. Only 18% of Moroccan species recorded are restricted to North Africa and 8% are Moroccan single-country endemics (81 species). Afrotropical elements in the Moroccan fauna are few, with only 3% of Morocco species co-occuring in that region. This checklist is intended to stimulate new regional research on bees including their taxonomy and biogeography. As many groups of bees have been understudied, discovery of new species for science and new records for the country can be expected. Additional research including inventorying, monitoring, and integrative taxonomic studies are needed to develop a comprehensive strategy for bee conservation in Morocco.


Subject(s)
Bees , Hymenoptera , Animals , Base Sequence , Hymenoptera/genetics , Morocco
12.
Zootaxa ; 4608(3): zootaxa.4608.3.6, 2019 May 21.
Article in English | MEDLINE | ID: mdl-31717135

ABSTRACT

Two previously unknown species of the genus Pseudapis Kirby, 1900 are described and illustrated: Pseudapis neumayeri Bossert Pauly, sp. nov. (♂, ♀, Kenya, Tanzania), and P. crassivertex Bossert Pauly, sp. nov. (♂, ♀, Mali, Mauritania, Niger, Senegal). We provide diagnoses for the new species and report all currently available records. Lastly, we present a revised identification key for the African species of the genus.


Subject(s)
Hymenoptera , Animal Distribution , Animals , Bees , Kenya , Mauritania , Senegal , Tanzania
13.
Ecol Evol ; 8(13): 6827-6838, 2018 Jul.
Article in English | MEDLINE | ID: mdl-30038778

ABSTRACT

All over the world, pollinators are threatened by land-use change involving degradation of seminatural habitats or conversion into agricultural land. Such disturbance often leads to lowered pollinator abundance and/or diversity, which might reduce crop yield in adjacent agricultural areas. For West Africa, changes in bee communities across disturbance gradients from savanna to agricultural land are mainly unknown. In this study, we monitored for the impact of human disturbance on bee communities in savanna and crop fields. We chose three savanna areas of varying disturbance intensity (low, medium, and high) in the South Sudanian zone of Burkina Faso, based on land-use/land cover data via Landsat images, and selected nearby cotton and sesame fields. During 21 months covering two rainy and two dry seasons in 2014 and 2015, we captured bees using pan traps. Spatial and temporal patterns of bee species abundance, richness, evenness and community structure were assessed. In total, 35,469 bee specimens were caught on 12 savanna sites and 22 fields, comprising 97 species of 32 genera. Bee abundance was highest at intermediate disturbance in the rainy season. Species richness and evenness did not differ significantly. Bee communities at medium and highly disturbed savanna sites comprised only subsets of those at low disturbed sites. An across-habitat spillover of bees (mostly abundant social bee species) from savanna into crop fields was observed during the rainy season when crops are mass-flowering, whereas most savanna plants are not in bloom. Despite disturbance intensification, our findings suggest that wild bee communities can persist in anthropogenic landscapes and that some species even benefitted disproportionally. West African areas of crop production such as for cotton and sesame may serve as important food resources for bee species in times when resources in the savanna are scarce and receive at the same time considerable pollination service.

14.
Sensors (Basel) ; 17(2)2017 Feb 17.
Article in English | MEDLINE | ID: mdl-28218674

ABSTRACT

This paper presents a focused review on the nanomaterials and associated transduction schemes that have been developed for the selective detection of hydrogen sulfide. It presents a quite comprehensive overview of the latest developments, briefly discusses the hydrogen sulfide detection mechanisms, identifying the reasons for the selectivity (or lack of) observed experimentally. It critically reviews performance, shortcomings, and identifies missing or overlooked important aspects. It identifies the most mature/promising materials and approaches for achieving inexpensive hydrogen sulfide sensors that could be employed in widespread, miniaturized, and inexpensive detectors and, suggests what research should be undertaken for ensuring that requirements are met.

15.
Zootaxa ; 4162(2): 225-44, 2016 Sep 09.
Article in English | MEDLINE | ID: mdl-27615971

ABSTRACT

This study presents the first checklist of the bees of the Maltese Islands and includes notes on the distribution of each species. A total of 95 species belonging to five bee families are recorded: Andrenidae (17 species), Apidae (34 species), Colletidae (6 species), Halictidae (15 species) and Megachilidae (23 species). Lasioglossum callizonium (Pérez, 1896) is recorded for the first time from the Maltese Islands. Records of three previously reported species are listed as dubious. The bee fauna of the Maltese Archipelago is dominated by widespread West-Palaearctic species, and most of the species recorded are also found in the Western Mediterranean Basin. Bees that have been recorded from Malta are also known from Southern Europe. The study provides a biogeographical analysis of the Maltese bee fauna, and discusses the conservation of this group and their important role in the delivery of ecosystem services in the Maltese Islands.


Subject(s)
Bees/anatomy & histology , Bees/classification , Animal Distribution/physiology , Animals , Bees/physiology , Female , Male , Mediterranean Islands , Species Specificity
16.
Biosensors (Basel) ; 6(3)2016 Sep 01.
Article in English | MEDLINE | ID: mdl-27598214

ABSTRACT

Here, we report on the use of electrochemical methods for the detection of volatiles fatty acids (VFAs), namely acetic acid. We used tetra-tert-butyl phthalocyanine (PcH2-tBu) as the sensing material and investigated its electroanalytical properties by means of cyclic voltammetry (CV) and square wave voltammetry (SWV). To realize the electrochemical sensing system, the PcH2-tBu has been dropcast-deposited on carbon (C) orgold (Au)screen-printed electrodes (SPEs) and characterized by cyclic voltammetry and scanning electron microscopy (SEM). The SEM analysis reveals that the PcH2-tBu forms mainly aggregates on the SPEs. The modified electrodes are used for the detection of acetic acid and present a linear current increase when the acetic acid concentration increases. The Cmodified electrode presents a limit of detection (LOD) of 25.77 mM in the range of 100 mM-400 mM, while the Aumodified electrode presents an LOD averaging 40.89 mM in the range of 50 mM-300 mM. When the experiment is realized in a buffered condition, theCmodified electrode presents a lower LOD, which averagesthe 7.76 mM. A pronounced signal decay attributed to an electrode alteration is observed in the case of the gold electrode. This electrode alteration severely affects the coating stability. This alteration is less perceptible in the case of the carbon electrode.


Subject(s)
Biosensing Techniques , Electrochemical Techniques , Electrodes , Acetic Acid/analysis , Indoles/analysis , Isoindoles , Limit of Detection
17.
Zootaxa ; 4034(2): 257-90, 2015 Oct 29.
Article in English | MEDLINE | ID: mdl-26624441

ABSTRACT

Several forms or variants have long been recognized in the West Palearctic sweat bee Seladonia smaragdula (Vachal, 1895). Using DNA barcoding and morphological characters, primarily of the male genitalia, these variants are here recognized and described as five new species: S. gemmella Pauly sp. nov., S. submediterranea Pauly sp. nov., S. orientana Pauly & Devalez sp. nov., S. phryganica Pauly & Devalez sp. nov., and S. cretella Pauly & Devalez sp. nov. Also, we designate a lectotype for Halictus smaragdulus Vachal, consider Seladonia butea (Warncke, 1975) and S. morinella (Warncke, 1975) as nomina dubia, and discuss the identity of the Seladonia specimens from Australia currently determined as S. smaragdula.


Subject(s)
Bees/classification , Bees/genetics , Animal Distribution , Animal Structures/anatomy & histology , Animal Structures/growth & development , Animals , Bees/anatomy & histology , Bees/growth & development , Body Size , DNA Barcoding, Taxonomic , Ecosystem , Female , Genitalia, Male/anatomy & histology , Genitalia, Male/growth & development , Male , Organ Size , Phylogeny
18.
Zootaxa ; 4021(1): 119-55, 2015 Sep 24.
Article in English | MEDLINE | ID: mdl-26624122

ABSTRACT

Sawflies were collected in Ethiopia during 2010-2013. Three species represent new records for the country: Arge deckerti Koch, 2005, Athalia excisa Koch, 2006 and Xenapates nigrifrons Koch, 2012. Arge flavifrons Mocsáry, 1909, syn. n. and A. transvaalensis Cameron, 1911, syn. n. are subjective synonyms of A. micheli (Buysson, 1900) that is re-described here. Athalia fumosa Gribodo, 1879 sp. rev. is recognized as a valid species and is removed from synonymy with A. scioensis Gribodo, 1879. Distega braunsi Enslin, 1911 syn. n. and D. brunniventris Enslin, 1913 syn. n. are subjective synonyms of D. montium Konow, 1907. Pseudoneacidiophora Koch, 1998 is a new junior synonym of Kivua Forsius, 1934 (syn. n.), resulting in the new combination Kivua pleuritica (comb. n.) for Athalia pleuritica Forsius, 1927. Kivua camerunensis nom. n. is proposed for P. bicolor Koch, 1998 (preoccupied in Kivua by K. bicolor (Pasteels, 1949) (Bicrista bicolor Pasteels)), the second species formerly included in Pseudoneacidiophora. The female of Distega abyssinica Pasteels, 1955 is described for the first time. An annotated and illustrated list including six distribution maps is given for Ethiopian sawflies. It is composed of 34 species belonging to the genus Arge (Argidae), and seven genera of Tenthredinidae: Athalia (Athaliinae), Kivua, Neacidiophora, Xenapates (Allantinae), Distega, Trisodontophyes (Blennocampinae), and Dulophanes (Selandriinae). Some ecological aspects of Athalia species are discussed, especially for the most abundantly collected A. vollenhoveni Gribodo, 1879.


Subject(s)
Hymenoptera/anatomy & histology , Hymenoptera/classification , Animals , Ethiopia , Female , Forests , Male
19.
J Colloid Interface Sci ; 407: 39-46, 2013 Oct 01.
Article in English | MEDLINE | ID: mdl-23890592

ABSTRACT

In order to enhance the durability of chemical filters for ozone molecules, devoted to microsystem for the selective detection of NO2 in the environment, the adsorption of indigo molecules onto the surface of carbonaceous nanomaterials (multi-walled carbon nanotubes, a mixture of nanodisks/nanocones, nanofibres) was investigated. The surface of the multi-walled carbon nanotubes was coated by π-stacking with adsorbed indigo molecules. An excess of indigo has resulted in a biphasic sample where nanotubes covered with indigo coexist with free indigo particles. Although similar filtering yields toward O3 (close to 100%) and NO2 (around 0%) were obtained as compared to individual materials, the indigo/MWCNTs samples exhibit enhanced durability as chemical filter at high ozone concentration (1 ppm).


Subject(s)
Indoles/chemistry , Nanotubes, Carbon/chemistry , Nitrogen Dioxide/analysis , Adsorption , Microscopy, Electron, Scanning
20.
Zootaxa ; 3693: 267-92, 2013.
Article in English | MEDLINE | ID: mdl-26185847

ABSTRACT

The Ethiopian species of the bee genus Colletes are revised and redescribed to facilitate their identification and future research. Colletes langano Kuhlmann sp. n., C. aethiopicus Kuhlmann sp. n. and C. senkelensis Kuhlmann sp. n. are described as new. The females of C. abessinicus Friese 1915 and C. microdontus Cockerell 1937 and the males of C. rothschildi Vachal 1909 and C. somereni Cockerell 1947 are described for the first time. Colletes rufitarsis Friese 1909 is removed from the list of Ethiopian species so currently a total of eight Colletes species are known from this country. A key is provided to facilitate species identification.


Subject(s)
Animal Distribution/physiology , Bees/anatomy & histology , Bees/classification , Animals , Bees/physiology , Ethiopia , Female , Male , Species Specificity
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