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1.
Curr Res Food Sci ; 6: 100386, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36846470

RESUMO

The biodiversity of Ecuadorian stingless bees is almost 200 species. Traditional pot-honey harvest in Ecuador is mostly done from nests of the three genera selected here Geotrigona Moure, 1943, Melipona Illiger, 1806, and Scaptotrigona Moure, 1942. The 20 pot-honey samples collected from cerumen pots and three ethnic honeys "abeja de tierra", "bermejo", and "cushillomishki" were analyzed for qualitative and quantitative targeted 1H-NMR honey profiling, and for the Honey Authenticity Test by Interphase Emulsion (HATIE). Extensive data of targeted organic compounds (41 parameters) were identified, quantified, and described. The three honey types were compared by ANOVA. Amino acids, ethanol, hydroxymethylfurfural, aliphatic organic acids, sugars, and markers of botanical origin. The number of phases observed with the HATIE were one in Scaptotrigona and three in Geotrigona and Melipona honeys. Acetic acid (19.60 ± 1.45 g/kg) and lactic acid (24.30 ± 1.65 g/kg) were particularly high in Geotrigona honey (in contrast to 1.3 g/kg acetic acid and 1.6 g/kg lactic acid in Melipona and Scaptotrigona), and with the lowest fructose + glucose (18.39 ± 1.68) g/100g honey compared to Melipona (52.87 ± 1.75) and Scaptotrigona (52.17 ± 0.60). Three local honeys were tested using PCA (Principal Component Analysis), two were assigned with a correct declared bee origin, but "bermejo" was not a Melipona and grouped with the Scaptotrigona cluster. However after HCA (Hierarchical Cluster Analysis) the three honeys were positioned in the Melipona-Scaptotrigona cluster. This research supports targeted 1H-NMR-based profiling of pot-honey metabolomics approach for multi-parameter visualization of organic compounds, as well as descriptive and pertained multivariate statistics (HCA and PCA) to discriminate the stingless bee genus in a set of Geotrigona, Melipona and Scaptotrigona honey types. The NMR characterization of Ecuadorian honey produced by stingless bees emphasizes the need for regulatory norms. A final note on stingless bee markers in pot-honey metabolites which should be screened for those that may extract phylogenetic signals from nutritional traits of honey. Scaptotrigona vitorum honey revealed biosurfactant activity in the HATIE, originating a fingerprint Honey Biosurfactant Test (HBT) for the genus in this set of pot-honeys.

2.
Zookeys ; 857: 59-84, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31303805

RESUMO

Taxonomic notes are provided on species of the uncommonly encountered ripiphorid subfamily Pelecotominae. Zapotecotomasumichrasti gen. et sp. nov., is described from southern Mexico based on a unique male likely collected in the later part of the mid-19th Century. The discovery of additional species of the South African genus Clinops Gerstaecker permit a revised diagnosis and distinction of the group from the eastern Mediterranean genus Scotoscopus Brenske and Reitter, resurrected status. Two new species of Clinops are established: Clinopsinexpectatus sp. nov. (northeast of Durban near Swaziland) and C.perpessus sp. nov. (region of Durban), and Scotoscopusspectabilis (Schaufuss) is newly recorded for the Peloponnese in Greece.

3.
Zootaxa ; 4415(3): 513-532, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30313614

RESUMO

Males of the neotropical bee genus Ruizantheda Moure sensu lato (Halictinae: Caenohalictini) differ from those of other caenohalictine genera in having the outer gonostylar plate with a large membranous region that extends to the ventral region, and the ventral gonostylar lobe retrorse. These features permit the placement of six additional species described here, four of which are new, in the genus in this broader sense. The males of these six species share the following characteristics: profemur swollen; mesofemur exceedingly swollen; mesotibia slightly swollen with flat, minutely ridged ventral area and small apical tooth; S4 shortened medially, commonly largely hidden under S3, with transverse median depression and apical margin emarginate; apicolateral lobes of S4 with tuft of branched setae and stout, simple, recurved setae on margin; S5 with U-shaped gradulus and setal patch, sometimes inconspicuous; outer lateral expansion of penis valve bilobed, and median posterior margin of volsella strongly angulate. Together, these species constitute a new group within Ruizantheda and share with the previously known Ruizantheda inca Coelho, Felizardo, Engel, R. aerugineus Coelho, Felizardo, Engel, and R. kallos Coelho, Felizardo, Engel, a short outer gonostylar plate, terminating before the apex of the main gonostylar lobe as well as the presence of long setae on its dorsal surface. In other species of Ruizantheda the outer gonostylar plate extends beyond the apex of the main gonostylar lobe and lacks setae. The species comprising this distinctive subgroup of Ruizantheda, and treated herein, are: R. nigra n. sp., R. colombiana n. sp., R. venezuelana n. sp., R. baeri (Vachal) n. comb., R. pilosa n. sp., and R. gaullei (Vachal) n. comb. Two of the new species expand the distribution of the genus northward into Colombia and Venezuela. In addition to the description and illustration of the species, an updated key to the species of Ruizantheda s. l. is provided.


Assuntos
Besouros , Himenópteros , Animais , Abelhas , Colômbia , Masculino , Pênis , Venezuela
4.
Nat Commun ; 9(1): 4095, 2018 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-30291247

RESUMO

Directed placement of solution-based nanomaterials at predefined locations with nanoscale precision limits bottom-up integration in semiconductor process technology. We report a method for electric-field-assisted placement of nanomaterials from solution by means of large-scale graphene layers featuring nanoscale deposition sites. The structured graphene layers are prepared via either transfer or synthesis on standard substrates, and then are removed once nanomaterial deposition is completed, yielding material assemblies with nanoscale resolution that cover surface areas >1 mm2. In order to demonstrate the broad applicability, we have assembled representative zero-dimensional, one-dimensional, and two-dimensional semiconductors at predefined substrate locations and integrated them into nanoelectronic devices. Ultimately, this method opens a route to bottom-up integration of nanomaterials for industry-scale applications.

5.
Rev. bras. entomol ; Rev. bras. entomol;61(4): 318-322, Oct.-Dec. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-1045471

RESUMO

Abstract The first gynandromorph of the insect order Zoraptera is reported. A gynandromorph of Zorotypus brasiliensis Silvestri is described from a likely parthenogenetic population in the Atlantic Forest around the border of the Brazilian states of Minas Gerais, Rio de Janeiro, and São Paulo. As has been previously surmised for this species, the sample consisted of only females, tending to support the hypothesis of thelytokous parthenogenesis for this population. The gynandromorph is largely female in outward appearance, but exhibits male secondary sexual traits on the left side of the apical abdominal segments. The left (male) antenna consists of antennomeres of different proportions to those of the right (female) antenna. The internal genitalia and associated sclerites, however, are female although some are augmented in their form relative to normal-type females. Comments are made on possible factors resulting in the development of the gynandromorph. This is the 16th insect order with gynandromorphism reported.

6.
Sci Rep ; 7: 46317, 2017 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-28397869

RESUMO

Wettability is the affinity of a liquid for a solid surface. For energetic reasons, macroscopic drops of liquid form nearly spherical caps. The degree of wettability is then captured by the contact angle where the liquid-vapor interface meets the solid-liquid interface. As droplet volumes shrink to the scale of attoliters, however, surface interactions become significant, and droplets assume distorted shapes. In this regime, the contact angle becomes ambiguous, and a scalable metric for quantifying wettability is needed, especially given the emergence of technologies exploiting liquid-solid interactions at the nanoscale. Here we combine nanoscale experiments with molecular-level simulation to study the breakdown of spherical droplet shapes at small length scales. We demonstrate how measured droplet topographies increasingly reveal non-spherical features as volumes shrink. Ultimately, the nanoscale droplets flatten out to form layer-like molecular assemblies at the solid surface. For the lack of an identifiable contact angle at small scales, we introduce a droplet's adsorption energy density as a new metric for a liquid's affinity for a surface. We discover that extrapolating the macroscopic idealization of a drop to the nanoscale, though it does not geometrically resemble a realistic droplet, can nonetheless recover its adsorption energy if line tension is included.

7.
Nano Lett ; 17(5): 2741-2746, 2017 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-28414911

RESUMO

Analysis of nanoscale liquids, including wetting and flow phenomena, is a scientific challenge with far reaching implications for industrial technologies. We report the conception, development, and application of an integrated platform for the experimental characterization of liquids at the nanometer scale. The platform combines the functionalities of a two-dimensional electronic array of sensor devices with in situ application of highly sensitive optical microspectroscopy and atomic force microscopy. We demonstrate the performance capabilities of the platform with an embodiment based on an array of optically transparent graphene sensors. The application of electronic and optical sensing in the platform allows for differentiating between liquids electronically, for determining a liquid's molecular fingerprint, and for monitoring surface wetting dynamics in real time. In order to explore the platform's sensitivity limits, we record topographies and optical spectra of individual, spatially isolated sessile oil emulsion droplets having volumes of less than ten attoliters. The results demonstrate that integrated measurement functionalities based on two-dimensional materials have the potential to push lab-on-chip based analysis from the microscale to the nanoscale.

8.
Nanoscale ; 8(28): 13652-8, 2016 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-27366868

RESUMO

The investigation and control of liquid flow at the nanometer scale is a key area of applied research with high relevance to physics, chemistry, and biology. We introduce a method and a device that allows the spatial resolution of liquid flow by integrating an array of graphene-based magnetic (Hall) sensors that is used for tracking the movement of magnetic nanoparticles immersed in a liquid under investigation. With a novel device concept based on standard integration processes and experimentally verified material parameters, we numerically simulate the performance of a single sensor pixel, as well as the whole sensor array, for tracking magnetic nanoparticles having typical properties. The results demonstrate that the device enables (a) the detection of individual nanoparticles in the liquid with high accuracy and (b) the reconstruction of a particle's flow-driven trajectory across the integrated sensor array with sub-pixel precision as a function of time, in what we call the "Magnetic nanoparticle velocimetry" technique. Since the method does not rely on optical detection, potential lab-on-chip applications include particle tracking and flow analysis in opaque media at the sub-micron scale.

9.
Zootaxa ; 3889(1): 58-70, 2014 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-25544132

RESUMO

Males of Ruizantheda Moure sensu lato differ from males of other Caenohalictina in having the outer gonostylar plate with a large membranous region that extends to the ventral region, and the ventral gonostylus in the form of a retrorse lobe. These features permit the placement of three new species described here in the genus in this broader sense. However, despite having simple mandibles, they do not have the traits considered as apomorphies of Ruizantheda s. str. or Ruizantheda + Oragapostemon Cure by earlier authors, and neither do they possess features of Ruizanthedella Moure. Moreover, in the new species, the outer gonostylar plate is short, ending before the apex of the main gonostylar lobe and has long setae on its dorsal surface, while in other Ruizantheda, the outer gonostylar plate extends beyond the apex of the main gonostylar lobe and lacks setae. Additionally, two of the new species have a distribution different from those of most Ruizantheda-Ruizantheda inca n. sp. is found in Ancash, Peru and R. aerugineus n. sp. in the state of Minas Gerais, Brazil. Instead of including the three species in a new genus, we believe that it is more reasonable to maintain the status of Ruizantheda sensu Michener and until a new phylogenetic analysis of the entire subtribe, inclusive of the species newly established here, is completed. The three new species, known only by the male, are described and illustrated, and a key to the species of Ruizantheda s. l. is provided. The homologies between the gonostylar structures, mainly those related to the dorsal gonostylar process, of males of Ruizantheda, Caenohalictus Cameron, and Pseudagapostemon Schrottky are discussed.


Assuntos
Abelhas/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Abelhas/anatomia & histologia , Abelhas/crescimento & desenvolvimento , Tamanho Corporal , Brasil , Feminino , Masculino , Tamanho do Órgão , Peru
10.
Zookeys ; (426): 119-27, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25147461

RESUMO

A new species of the scelionine genus Macroteleia Westwood (Platygastridae s.l., Scelioninae) is described and figured from a female beautifully preserved in Middle Miocene amber from Peru. Macroteleia yaguarum Perrichot & Engel, sp. n., shows a unique combination of characters otherwise seen independently within its congeners. It is most similar to the modern M. surfacei Brues, but differs from it by the non-foveolate notauli, the contiguous punctures of the vertex, and the continuous propodeum. The new species is the first New World fossil of the genus, suggesting a Cretaceous origin for the group and a relatively old age of the South American, tropical African, and Australian faunas, and a younger age of the modern Holarctic faunas.

11.
Zookeys ; (222): 47-68, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23129986

RESUMO

Three new species of orchid bees are described and figured from the Amazon and Atlantic forests of Brazil. Euglossa clausisp. n., Euglossa moratoisp. n., and Euglossa pepeisp. n. are distinguished from their close congeners Euglossa crassipunctata Moure, Euglossa parvula Dressler, and Euglossa sapphirina Moure, previously placed in the subgenus Euglossa (Glossurella) Dressler, 1982, a demonstrably paraphyletic assemblage requiring serious reconsideration. Their affinities with related species are discussed and pertinent characters are figured.

12.
Zookeys ; (185): 41-53, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22577312

RESUMO

A third species of the rare augochlorine bee genus Chlerogelloides Engel et al. (Halictinae, Augochlorini) is described and figured. Chlerogelloides nexosasp. n. is most similar to the type species, Chlerogelloides femoralis Engel et al., in that both have modified midlegs in the males. The former, however, can be distinguished on the basis of its terminalia, which in some respects more closely resembles those of Chlerogelloides simplex Engel and Brooks. Brief comments on the secondary features of males and relationships of the genus are provided. A key to the species of the genus is provided and floral records of Cordia nodosa Lam. (Boraginaceae) and Gonzalagunia dicocca Cham. & Schltdl. (Rubiaceae) are noted.

13.
Zookeys ; (172): 77-87, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22448115

RESUMO

A new species of the Neotropical stingless bee genus Geotrigona Moure from the Caribbean coast of Colombia is described and figured. Geotrigona joearroyoisp. n. belongs to the fulvohirta species group and is distinguished on the basis of color and type of pubescence on the metasomal terga. New geographical records and an updated key to the species of Geotrigona are provided.

14.
Zookeys ; (111): 19-31, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21852936

RESUMO

A new study of a surviving syntype of Trigona meadewaldoi Cockerell, 1915, was undertaken and several widely employed names for Neotropical stingless bees recognized as junior synonyms. A lectotype is designated for Trigona meadewaldoi and the following new synonymies established: Tetragona francoi Moure, 1946, and Trigona (Frieseomelitta) freiremaiai Moure, 1963. These nomenclatural matters are here settled and the species thoroughly characterized in advance of a forthcoming phylogenetic consideration of the genus Frieseomelitta von Ihering, 1912.

15.
Zookeys ; (111): 33-40, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21852937

RESUMO

A new species of the cleptoparasitic bee genus Microsphecodes Eickwort and Stage (Halictinae: Halictini) is described and figured from a male and female collected in Jamaica. Microsphecodes xaymacensis Engel, sp. n., is distinguished from its congeners on the basis of integumental coloration and sculpturing, and form of the male pygidial plate and genitalia.

16.
Zookeys ; (86): 61-8, 2011 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-21594093

RESUMO

A new species of Lasioglossum Curtis subgenus Dialictus Robertson (Halictinae, Halictini) is described and figured from a series of female and males collected on Sombrero Island, Anguilla; the northernmost island of the Lesser Antilles. Lasioglossum (Dialictus) sombrerensesp. n. is distinguished from its congeners and the name made available for a forthcoming work on the arthropod diversity of Sombrero Island.

17.
Proc Biol Sci ; 278(1722): 3219-24, 2011 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-21429925

RESUMO

Despite centuries of research addressing amber and its various inclusions, relatively little is known about the specific events having stimulated the production of geologically relevant volumes of plant resin, ultimately yielding amber deposits. Although numerous hypotheses have invoked the role of insects, to date these have proven difficult to test. Here, we use the current mountain pine beetle outbreak in western Canada as an analogy for the effects of infestation on the stable isotopic composition of carbon in resins. We show that infestation results in a rapid (approx. 1 year) (13)C enrichment of fresh lodgepole pine resins, in a pattern directly comparable with that observed in resins collected from uninfested trees subjected to water stress. Furthermore, resin isotopic values are shown to track both the progression of infestation and instances of recovery. These findings can be extended to fossil resins, including Miocene amber from the Dominican Republic and Late Cretaceous New Jersey amber, revealing similar carbon-isotopic patterns between visually clean ambers and those associated with the attack of wood-boring insects. Plant exudate δ(13)C values constitute a sensitive monitor of ecological stress in both modern and ancient forest ecosystems, and provide considerable insight concerning the genesis of amber in the geological record.


Assuntos
Âmbar/química , Isótopos de Carbono/análise , Besouros/anatomia & histologia , Fósseis , Resinas Vegetais/química , Alberta , Animais , Besouros/química , República Dominicana , New Jersey , Pinus/química , Dinâmica Populacional
18.
Zookeys ; (153): 81-90, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22287912

RESUMO

The bee genus Chilicola Spinola (Xeromelissinae) is recorded from the State of Bahia, Brazil for the first time, based on a new species of the megalostigma group of the subgenus Hylaeosoma Ashmead. Chilicola (Hylaeosoma) kevanisp. n. is described and figured from males collected in Wesceslau Guimarães, Bahia. The species can be distinguished on the basis of coloration, size, integumental sculpturing, and structure of the hidden metasomal sterna and genitalia. A revised key to the species of the megalostigma group is provided.

19.
Zookeys ; (159): 49-63, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22303114

RESUMO

Euglossa williamsisp. n. is here described from the lowland Amazonian region in Ecuador and Peru, and as part of a small species assemblage within Euglossa consisting of Euglossa dodsoni Moure and Euglossa obtusa Dressler. An identification key to the males of the group is provided plus detailed figures of the new species and representative illustrations for the others. A brief discussion of the taxonomic and biogeographical implications of the new species is provided. New records in Honduras and Nicaragua are provided for the related Euglossa dodsoni.

20.
Naturwissenschaften ; 96(9): 1121-6, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19547945

RESUMO

Complex ethological adaptations and intraspecific interactions leave few fossil traces. We document three Dominican (20 million years old [myo]) and Baltic (45 myo) amber fossils that exhibit firm evidence of highly integrated interactions between mothers and offspring in the diverse camptosomate lineage of beetles (Chrysomelidae, leaf beetles). As in contemporary species, these hard cases were initially constructed by mothers, then inherited and retained by offspring, which then elaborate this protective domicile with an unusual but economical building material, their feces. The three fossils are classified in the Subfamily Cryptocephalinae; two are classified in the tribe Chlamisini based on morphological evidence-the flattened head lacking a sharp keel and long legs with simple recurved untoothed claws. These diagnostic features are not clearly visible in the third specimen to permit more refined identification. These fossils provide more precise paleontological dating of tribal nodes within the cryptocephaline radiation of leaf beetles. These fossils are the first and earliest evidence of mother-offspring interaction, building behavior, and fecal recycling in Camptosomata beetles and of inheritance of architectural structures in beetles.


Assuntos
Âmbar , Besouros/anatomia & histologia , Animais , Comportamento Animal , Besouros/fisiologia , Feminino , Fósseis , Larva/fisiologia , Comportamento Materno , Folhas de Planta
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