Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Zootaxa ; 4969(2): 392400, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-34186923

RESUMO

The study of the lectotype of Sehirus fuscipennis Horváth, 1899 showed that this specimen is conspecific with Canthophorus maculipes sensu Aukema Constant, 2016 and Adomerus maculipes sensu Gapon, 2018. To promote stability of nomenclature, the neotype of Cydnus maculipes Mulsant et Rey 1852 is designated instead of the lost syntypes. The name Sehirus aeneus Walker, 1867 is placed in synonymy with Adomerus maculipes (Mulsant et Rey, 1852). The name Adomerus fuscipennis (Horváth, 1899), stat. resurr. is reinstated. Colouration of the hemelytra, the structure of the parameres and aedeagi of the holotype of S. aeneus Walker, 1867 (female), of a male of A. maculipes, being topotypic with the latter, and of the lectotype of S. fuscipennis Horváth, 1899 are compared with each other and with descriptions of the terminalia of both species, recently published by the second author based on material from different localities. A map of the distribution of both species is given according to the literature data and studied collection materials.


Assuntos
Heterópteros/classificação , Animais , Feminino , Masculino
2.
Ecology ; 96(2): 518-31, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26240873

RESUMO

In the face of ongoing habitat fragmentation, species-area relationships (SARs) have gained renewed interest and are increasingly used to set conservation priorities. An important question is how large habitat areas need to be to optimize biodiversity conservation. The relationship between area and species richness is explained by colonization-extinction dynamics, whereby smaller sites harbor smaller populations, which are more prone to extinction than the larger populations sustained by larger sites. These colonization-extinction dynamics are predicted to vary with trophic rank, habitat affinity, and dispersal ability of the species. However, empirical evidence for the effect of these species characteristics on SARs remains inconclusive. In this study we used carabid beetle data from 58 calcareous grassland sites to investigate how calcareous grassland area affects species richness and activity density for species differing in trophic rank, habitat affinity, and dispersal ability. In addition, we investigated how SARs are affected by the availability of additional calcareous grassland in the surrounding landscape. Beetle species richness and activity density increased with calcareous grassland area for zoophagous species that are specialists for dry grasslands and, to a lesser extent, for zoophagous habitat generalists. Phytophagous species and zoophagous forest and wet-grassland specialists were not affected by calcareous grassland area. The dependence of species on large single sites increased with decreasing dispersal ability for species already vulnerable to calcareous grassland area. Additional calcareous grassland in the landscape had a positive effect on local species richness of both dry-grassland specialists and generalists, but this effect was restricted to a few hundred meters. Our results demonstrate that SARs are affected by trophic rank, habitat affinity, and dispersal ability. These species characteristics do not operate independently, but should be viewed in concert. In addition, species' responses depend on the landscape context. Our study suggests that the impact of habitat area on trophic interactions may be larger than previously anticipated. In small habitat fragments surrounded by a hostile matrix, food chains may be strongly disrupted. This highlights the need to conserve continuous calcareous grassland patches of at least several hectares in size.


Assuntos
Distribuição Animal , Besouros/fisiologia , Ecossistema , Animais , Conservação dos Recursos Naturais , Especificidade da Espécie
3.
Am J Bot ; 98(7): 1095-103, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21700799

RESUMO

PREMISE OF THE STUDY: Although many species in the orchid genus Coelogyne are horticulturally popular, hardly anything is known about their pollination. Pollinators of three species were observed in the field in Nepal. This information is urgently needed because many orchid species in Nepal are endangered. Whether the exudates produced by extrafloral nectaries played a role in protection against herbivory was also investigated. METHODS: Pollinators of C. flaccida, C. nitida, and Otochilus albus were filmed, captured, and identified. Ant surveys and exclusion experiments were carried out. To investigate whether pollinators are needed for fruit set, plants were wrapped in mesh wire bags. Inflorescence stems were examined with microscopy. Fehling's reagent was used to detect sugars in extrafloral exudates. KEY RESULTS: Coelogyne flaccida and C. nitida need pollinators to set fruit and are pollinated by wild bees identified as Apis cerana. Otochilus albus was found to be pollinated by Bombus kashmirensis. Extrafloral nectar was found to be exuded by nectary-modified stomata and contained high amounts of sugars. Different species of ants were observed collecting these exudates. A significant difference was found in damage inflicted by flower and leaf-eating beetles between C. nitida plants living in trees with ant nests and those in ant-free trees. CONCLUSIONS: Floral syndromes include scented and colored trap flowers without reward to their pollinators. All orchids investigated exude extrafloral nectar by nectary-modified stomata. This nectar was found to flow from the phloem to the stomata through intercellular spaces in the outer parenchymatous layer of the inflorescence.


Assuntos
Herbivoria/fisiologia , Orchidaceae/fisiologia , Polinização/fisiologia , Animais , Formigas/fisiologia , Abelhas/fisiologia , Besouros/fisiologia , Inflorescência/citologia , Inflorescência/ultraestrutura , Nepal , Orchidaceae/parasitologia , Exsudatos de Plantas/metabolismo , Néctar de Plantas/metabolismo , Estômatos de Plantas/fisiologia , Estômatos de Plantas/ultraestrutura , Especificidade da Espécie
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA