Water-filled tree hollows constitute phytotelmata that harbor specialized organisms. One striking example of extreme adaptation to these microhabitats is the case of the microcrustacean Micromoina arboricola, which has been found inhabiting the hollow of a single tree individual in the Atlantic Forest. We investigated the spatial distribution and influence of microhabitat characteristics such as hollow volume and height from the ground in the occurrence of M.
View Article and Find Full Text PDFResupination refers to the developmental orientation changes of flowers through ≈180º, leaving them effectively upside-down. It is a widespread trait present in 14 angiosperm families, including the Orchidaceae, where it is a gravitropic phenomenon actively controlled by auxins. Here, we demonstrate that the passive gravitational pull on flower parts can have an additional influence on resupination.
View Article and Find Full Text PDFPredation pressure influences animal behaviour in relation to feeding, exposure to predators and habitat use. In the presence of a predator, prey usually decreases feeding and activity, avoiding predation-risk areas. This study evaluated the visual effects of a predator fish (red-bellied piranha Pygocentrus nattereri) on the behaviour and habitat use of Macrobrachium jelskii prawn.
View Article and Find Full Text PDFBackground And Aims: Trap flowers are fascinating cases of adaptation, often linked to oviposition-site mimicry systems. Some trap flowers do not imprison pollinators for a pre-determined period, but rather force them to move through a specific path, manipulating their movements in a way that culminates in pollen transfer, often as they leave through a secondary opening.
Methods: We investigated the previously unknown pollination system of the lady's slipper orchid Phragmipedium vittatum and assessed the function of micro-morphological traits of its trap flowers.
Plant galls are generated by the stimuli of gall-inducing organisms on their hosts, creating gall morphotypes that vary in color, shape, size, and tissue organization. Herein, we propose to compare the structural features of gall morphotypes on the superhost Croton floribundus (Euphorbiaceae) in order to recognize gall morphospecies, i.e.
View Article and Find Full Text PDFNaturwissenschaften
September 2021
Florivores and rainfall generally have negative impacts on plant fecundity. However, in some cases, they can mediate fruit set. Some plants face severe pollen-limited fecundity and any additional fruit set, even if from self-pollination, can be advantageous.
View Article and Find Full Text PDFThe chemical composition of the cell walls strongly affects water permeability and storage in root tissues. Since epiphytic orchids live in a habitat with a highly fluctuating water supply, the root cell walls are functionally important. In the present study, we used histochemistry and immunocytochemistry techniques in order to determine the composition of the cell walls of root tissues of 18 epiphytic species belonging to seven subtribes across the Orchidaceae.
View Article and Find Full Text PDFThe original version of this article unfortunately contains an error. The correct caption of Figures 2 and 3 are shown in this paper.
View Article and Find Full Text PDFInsect-induced galls usually develop nutritional cells, which they induce and consume directly, and any metabolic modification of those cells may reflect changes of the insect's own metabolism. The system Palaeomystella oligophaga (Lepidoptera)-Macairea radula (Melastomataceae) presents a series of natural enemies, including parasitoids and cecidophages that can function as a natural experiment, respectively removing the specific galling feeding stimulus and providing a nonspecific one. Considering that the process of induction and maintenance of gall tissues strictly depends on the constant specific stimulus of galling, question I:What kind of metabolic changes these different groups of natural enemies can promote in chemical and structural composition of these galls? II: How the specialized tissues are metabolically dependent on the constant specific stimulus of galling in latter stages of gall development? Galls without natural enemies, with parasitoids or cecidophages in larvae or pupae stages were analyzed through histochemistry and cytological profiles and all compared to galls in natural senescence state.
View Article and Find Full Text PDFSeveral studies have suggested reasons why galls have conspicuous colours, but none of the ideas have been confirmed. However, what if the vibrant colours of some galls are explained simply by the effect of light exposure? This may lead to anthocyanin accumulation, functioning as a defence mechanism against the effects of high light. We studied the globoid galls induced by Cecidomyiidae (Diptera) on Qualea parviflora (Vochysiaceae), relating anthocyanin accumulation and chlorophyll fluorescence parameters to light incidence in abaxial and adaxial galls.
View Article and Find Full Text PDFThe coexistence of phylogenetically related species is an attractive topic because of the potentially intense interspecific competition. The most often investigated mechanisms mediating coexistence of these species are environmental filtering and niche partitioning. However, the role of other factors, such as species-specific parasites, is still poorly understood.
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