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1.
Phys Rev Lett ; 128(8): 087401, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35275663

RESUMO

Excitons in atomically thin transition-metal dichalcogenides (TMDs) have been established as an attractive platform to explore polaritonic physics, owing to their enormous binding energies and giant oscillator strength. Basic spectral features of exciton polaritons in TMD microcavities, thus far, were conventionally explained via two-coupled-oscillator models. This ignores, however, the impact of phonons on the polariton energy structure. Here we establish and quantify the threefold coupling between excitons, cavity photons, and phonons. For this purpose, we employ energy-momentum-resolved photoluminescence and spatially resolved coherent two-dimensional spectroscopy to investigate the spectral properties of a high-quality-factor microcavity with an embedded WSe_{2} van der Waals heterostructure at room temperature. Our approach reveals a rich multibranch structure which thus far has not been captured in previous experiments. Simulation of the data reveals hybridized exciton-photon-phonon states, providing new physical insight into the exciton polariton system based on layered TMDs.

2.
New Phytol ; 206(1): 342-351, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25488155

RESUMO

Pollination of several angiosperms is based on deceit. In such systems, the flowers advertise a reward that ultimately is not provided. We report on a previously unknown pollination/mimicry system discovered in deceptive Aristolochia rotunda (Aristolochiaceae). Pollinators were collected in the natural habitat and identified. Flower scent and the volatiles of insects (models) potentially mimicked were analyzed by chemical analytical techniques. Electrophysiological and behavioral tests on the pollinators identified the components that mediate the plant-pollinator interaction and revealed the model of the mimicry system. The main pollinators of A. rotunda were female Chloropidae. They are food thieves that feed on secretions of true bugs (Miridae) while these are eaten by arthropod predators. Freshly killed mirids and Aristolochia flowers released the same scent components that chloropids use to find their food sources. Aristolochia exploits these components to deceive their chloropid pollinators. Aristolochia and other trap flowers were believed to lure saprophilous flies and mimic brood sites of pollinators. We demonstrate for A. rotunda, and hypothesize for other deceptive angiosperms, the evolution of a different, kleptomyiophilous pollination strategy. It involves scent mimicry and the exploitation of kleptoparasitic flies as pollinators. Our findings suggest a reconsideration of plants assumed to show sapromyiophilous pollination.


Assuntos
Aristolochia/química , Dípteros/fisiologia , Insetos/fisiologia , Óleos Voláteis/química , Animais , Aristolochia/fisiologia , Evolução Biológica , Ecossistema , Feminino , Flores/química , Flores/fisiologia , Hemípteros/fisiologia , Pólen/fisiologia , Polinização , Reprodução , Especificidade da Espécie
3.
Zootaxa ; 5389(3): 343-361, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38221019

RESUMO

The identity of Syllepte Hbner, 181921 is revised by designating a neotype from Neomabra Dognin, 1905, rev. syn., for the type species S. incomptalis Hbner, 181921 because the original type material is lost, and we consider it to be congeneric with Syllepte. We redescribe Syllepte based on S. incomptalis and S. nitidalis (Dognin, 1905), rev. comb., and place Syllepte in Agroterini Acloque, 1897, and consequently synonymize Syleptinae [sic] Swinhoe, 1900, syn. rev., with Agroterini. Pantographa Lederer, 1863 and Micromartinia Amsel, 1957 are redescribed, diagnosed, and restored to their status as valid genera, rev. stat., also in the tribe Agroterini. We designate lectotypes for Neomabra nitidalis Dognin, 1905, new lectotype, rev. comb., and Pantographa scripturalis (Guene, 1854), new lectotype, rev. stat., to stabilize the names of these species. Pantographa is compared to Haritalodes Warren, 1890. We newly combine Pantographa gorgonalis Druce, 1895, n. comb., rev. stat., and Pilocrocis cyrisalis (Druce, 1895), n. comb., with Micromartinia. One hundred and ninety-six species are listed that remain misplaced in the polyphyletic Syllepte and need further revision to determine their identity and proper generic placement.


Assuntos
Lepidópteros , Mariposas , Aves Canoras , Animais
4.
Insects ; 12(3)2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33804789

RESUMO

In a cross-sectional survey study (N = 116), volunteers of the project Insects of Saxony were asked about their current and past volunteering activities, their motivations, their rating of organisational offers, their knowledge, their satisfaction with the project and their personal contribution, and their intended future involvement. Participants in the study were mostly male, well-educated, over 50 years old, and had been volunteering in biodiversity projects for a long time. They were driven by both pro-social (altruistic) and self-serving (egoistic) motivations, but rated the pro-social functions as more important for their engagement. Communication and feedback were rated the most important organisational offers. Participants also reported a knowledge increase during project participation. While the volunteers were satisfied with the overall project, they were significantly less content with their own contribution. Results from the survey were followed up with a group discussion (N = 60). The anecdotes revealed the participants' regret of not having more time for their hobby, and they emphasised the challenges that arise from the different scientific approaches of the various disciplines. Most participants indicated that they want to continue their volunteering. Implications for measuring motivations in citizen science projects and for volunteer management are discussed.

5.
Nat Commun ; 12(1): 954, 2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33574235

RESUMO

Single-layer transition metal dichalcogenides are at the center of an ever increasing research effort both in terms of fundamental physics and applications. Exciton-phonon coupling plays a key role in determining the (opto)electronic properties of these materials. However, the exciton-phonon coupling strength has not been measured at room temperature. Here, we use two-dimensional micro-spectroscopy to determine exciton-phonon coupling of single-layer MoSe2. We detect beating signals as a function of waiting time induced by the coupling between A excitons and A'1 optical phonons. Analysis of beating maps combined with simulations provides the exciton-phonon coupling. We get a Huang-Rhys factor ~1, larger than in most other inorganic semiconductor nanostructures. Our technique offers a unique tool to measure exciton-phonon coupling also in other heterogeneous semiconducting systems, with a spatial resolution ~260 nm, and provides design-relevant parameters for the development of optoelectronic devices.

6.
Biodivers Data J ; 8: e52621, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32733140

RESUMO

The New Zealand fauna of snout moths (Pyraloidea) predominantly consists of endemic species. During 2017 and 2018, 56 species of Pyraloidea in 1,749 individuals were collected at 14 localities. All species were screened for Wolbachia-infection, with specimens of eight species (14%) being positive, of which six species belong to Scopariinae. This is the first record of Wolbachia-infection amongst New Zealand Lepidoptera. The most common pyraloid species, Eudonia submarginalis and Orocrambus flexuosellus, were analysed for a larger set of individuals looking for sex ratio and Wolbachia-infection. There is a sex ratio bias towards females in both species, but it varies in space and time. Wolbachia is found in all populations of E. submarginalis with 10-80% of the tested individuals being positive, depending on locality. No Wolbachia-infection has been found in O. flexuosellus. Thus, sex ratio bias might be linked to Wolbachia-infection in E. submarginalis, but not in O. flexuosellus.

7.
Biodivers Data J ; 8: e58841, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33293886

RESUMO

Identification of pyraloid species is often hampered by highly similar external morphology requiring microscopic dissection of genitalia. This becomes especially obvious when mass samples from ecological studies or insect monitoring have to be analysed. DNA barcode sequences could accelerate identification, but are not available for most pyraloid species from New Zealand. Hence, we are presenting a first DNA-barcode library for this group, providing 440 COI barcodes (cytochrome C oxidase I sequences) for 73 morphologically-identified species, which is 29% of Pyraloidea known from New Zealand. Results are analysed using the Barcode Index Number system (BIN) of BOLD and the Automatic Barcode Gap Discovery method (ABGD). Using BIN, the 440 barcodes reveal 82 clusters. A perfect match between BIN assignment and morphological identification was found for 63 species (86.3%). Four species (5.5%) share BINs, each with two species in one BIN, of which Glaucocharis epiphaea and Glaucocharis harmonica even share the same barcode. In contrast, six species (8.2%) split into two or more BINs, with the highest number of five BINs for Orocrambus ramosellus. The interspecific variation of all collected specimens of New Zealand Pyraloidea averages 12.54%. There are deep intraspecific divergences (> 2%) in seven species, for instance Orocrambus vulgaris with up to 6.6% and Scoparia ustimacula with 5.5%. Using ABGD, the 440 barcodes reveal 71 or 88 operational taxonomic units (OTUs), depending on the preferred partition. A perfect match between OTU and morphological identification was found for 56 species (76.7%) or 62 species (84.9%). ABGD delivers four or seven species sharing OTUs and four or ten species split into more than one OTU. Morphological re-examination, as well as the analysis of a concatenated dataset of COI and the nuclear markers EF1α and GADPH for species split into more than one BIN or OTU, do not support a higher number of species. Likewise, there is no evidence for Wolbachia infection as a trigger for these sequence variations.

8.
Zookeys ; 907: 1-99, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32063727

RESUMO

Hoploscopa Meyrick (Lepidoptera: Crambidae) is a fern-feeding genus found in montane areas of South-East Asia and Melanesia, eastwards up to the Samoan Islands. It includes sixteen described species, with at least 70 further undescribed species known from scientific collections. An iterative approach including morphological and molecular characters was used in order to explore the diversity of Hoploscopa. The hitherto described species are revised, and descriptions authored by T. Léger and M. Nuss are provided for an additional 26 new species: H. agtuuganonensis sp. nov., H. albipuncta sp. nov., H. albomaculata sp. nov., H. anacantha sp. nov., H. boleta sp. nov., H. cynodonta sp. nov., H. danaoensis sp. nov., H. gombongi sp. nov., H. gracilis sp. nov., H. ignitamaculae sp. nov., H. isarogensis sp. nov., H. jubata sp. nov., H. kelama sp. nov., H. kinabaluensis sp. nov., H. mallyi sp. nov., H. marijoweissae sp. nov., H. matheae sp. nov., H. niveofascia sp. nov., H. pangrangoensis sp. nov., H. parvimacula sp. nov., H. pseudometacrossa sp. nov., H. sepanggi sp. nov., H. sumatrensis sp. nov., H. titika sp. nov., H. tonsepi sp. nov., H. ypsilon sp. nov. Using a protocol specific for the amplification of DNA from old museum specimens, we recovered 101 COI barcodes for all but one of the newly described species, with 76 being barcode compliant (>487 bp). Species delimitation analyses suggest cryptic diversity, with six cases reflecting allopatric divergence, and two further cases found in sympatry.

9.
Zookeys ; (746): 51-90, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29674896

RESUMO

The analysis of mitochondrial COI data for the European-Centroasian montane Udea alpinalis species group finds deep intraspecific splits. Specimens of U. austriacalis and U. rhododendronalis separate into several biogeographical groups. These allopatric groups are not recovered in the analyses of the two nuclear markers wingless and Elongation factor 1-alpha, except for U. austriacalis from the Pyrenees and the French Massif Central. The latter populations are also morphologically distinct and conspecific with Scopula donzelalis Guenée, 1854, which is removed from synonymy and reinstated as Udea donzelalis (Guenée, 1854) stat. rev. Furthermore, Udea altaica (Zerny, 1914), stat. n. from the Mongolian central Altai mountains, U. juldusalis (Zerny, 1914), stat. n. from the Tian Shan mountains of Kazakhstan, Kyrgyzstan and NW China, and U. plumbalis (Zerny, 1914), stat. n. from the Sayan Mountains of Northern Mongolia are raised to species level, and lectotypes are designated. Evidence of introgression of U. alpinalis into U. uliginosalis at three localities in the Central Alps is presented. A screening for Wolbachia using the markers wsp, gatB and ftsZ was negative for the U. alpinalis species group, but Wolbachia was found in single specimens of U. fulvalis and U. olivalis (both in the U. numeralis species group). We do not find evidence for the conjecture of several authors of additional subspecies in U. rhododendronalis, and synonymise U. rhododendronalis luquetalis Leraut, 1996, syn. n. and U. r. ventosalis Leraut, 1996, syn. n. with the nominal U. rhododendronalis (Duponchel, 1834).

10.
Zookeys ; (472): 117-62, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25632252

RESUMO

The larvae of the Old World genera Leucinodes Guenée, 1854 and Sceliodes Guenée, 1854 are internal feeders in the fruits of Solanaceae, causing economic damage to cultivated plants like Solanummelongena and Solanumaethiopicum. In sub-Saharan Africa five nominal species of Leucinodes and one of Sceliodes occur. One of these species, the eggplant fruit and shoot borer Leucinodesorbonalis Guenée, 1854, is regarded as regularly intercepted from Africa and Asia in Europe, North and South America and is therefore a quarantine pest on these continents. We investigate the taxonomy of African Leucinodes and Sceliodes based on morphological characters in wing pattern, genitalia and larvae, as well as mitochondrial DNA, providing these data for identification of all life stages. The results suggest that both genera are congeneric, with Sceliodes syn. n. established as junior subjective synonym of Leucinodes. Leucinodesorbonalis is described from Asia and none of the samples investigated from Africa belong to this species. Instead, sub-Saharan Africa harbours a complex of eight endemic Leucinodes species. Among the former nominal species of Leucinodes (and Sceliodes) from Africa, only Leucinodeslaisalis (Walker, 1859), comb. n. (Sceliodes) is confirmed, with Leucinodestranslucidalis Gaede, 1917, syn. n. as a junior subjective synonym. The other African Leucinodes species were unknown to science and are described as new: Leucinodesafricensis sp. n., Leucinodesethiopica sp. n., Leucinodeskenyensis sp. n., Leucinodesmalawiensis sp. n., Leucinodespseudorbonalis sp. n., Leucinodesrimavallis sp. n. and Leucinodesugandensis sp. n. An identification key based on male genitalia is provided for the African Leucinodes species. Most imports of Leucinodes specimens from Africa into Europe refer to Leucinodesafricensis, which has been frequently imported with fruits during the last 50 years. In contrast, Leucinodeslaisalis has been much less frequently recorded, and Leucinodespseudorbonalis as well as Leucinodesrimavallis only very recently in fruit imports from Uganda. Accordingly, interceptions of Leucinodes from Africa into other continents will need to be re-investigated for their species identity and will likely require, at least in parts, revisions of the quarantine regulations. The following African taxa are excluded from Leucinodes: Hyperanalyta Strand, 1918, syn. rev. as revised synonym of Analyta Lederer, 1863; Analytaapicalis (Hampson, 1896), comb. n. (Leucinodes); Lygropiaaureomarginalis (Gaede, 1916), comb. n. (Leucinodes); Sylleptehemichionalis Mabille, 1900, comb. rev., Sylleptehemichionalisidalis Viette, 1958, comb. rev. and Sylleptevagans (Tutt, 1890), comb. n. (Aphytoceros). Deanolisiriocapna (Meyrick, 1938), comb. n. from Indonesia is originally described and misplaced in Sceliodes, and Leucinodescordalis (Doubleday, 1843), comb. n. (Margaritia) from New Zealand, Leucinodesraondry (Viette, 1981), comb. n. (Daraba) from Madagascar as well as Leucinodesgrisealis (Kenrick, 1912), comb. n. (Sceliodes) from New Guinea are transferred from Sceliodes to Leucinodes. While Leucinodes is now revised from Africa, it still needs further revision in Asia.

11.
Zookeys ; (375): 15-73, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24526844

RESUMO

The Neotropical genus Catharylla Zeller, 1863 (type species: Crambus tenellus Zeller, 1839) is redescribed. Catharylla contiguella Zeller, 1872, C. interrupta Zeller, 1866 and Myelois sericina Zeller, 1881, included by Munroe (1995) in Catharylla, are moved to Argyria Hübner. Catharylla paulella Schaus, 1922 and C. tenellus (Zeller, 1839) are redescribed. Six new species are described by Léger and Landry: C. bijuga, C. chelicerata, C. coronata, C. gigantea, C. mayrabonillae and C. serrabonita. The phylogenetic relationships were investigated using morphological as well as molecular data (COI, wingless, EF-1α genes). The median and subterminal transverse lines of the forewing as well as the short anterior and posterior apophyses of the female genitalia are characteristic of the genus. The monophyly of Catharylla was recovered in all phylogenetic analyses of the molecular and the combined datasets, with three morphological apomorphies highlighted. Phylogenetic analyses of the morphology of the two sexes recovered three separate species groups within Catharylla: the chelicerata, the mayrabonillae, and the tenellus species groups. The possible position of Micrelephas Schaus, 1922 as sister to Catharylla, based on both morphological and molecular data, and the status of tribe Argyriini are discussed. The biogeographical data indicate that the chelicerata species group is restricted to the Guyanas and the Amazonian regions whereas the tenellus group is restricted to the Atlantic Forest in the South-Eastern part of Brazil. The mayrabonillae group is widespread from Costa Rica to South Bolivia with an allopatric distribution of the two species. COI barcode sequences indicate relatively strong divergence within C. bijuga, C. mayrabonillae, C. serrabonita and C. tenellus.

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