Search

The article evaluates the effects of spatial and environmental variables in the distribution of 11 anuran species at a forest in central Amazonia. It examines the species found breeding in ponds, phytotelmata and streams, the role of abiotic and biotic factors in abundance of the species and pattern of occurrence at watersheds. It focuses on the abundance of the species Vitreorana oyampiensis, Osteocephalus oophagus and Trachycephalus resinifictrix, including the importance of the forest to their survival.

Summary [ABSTRACT FROM AUTHOR]

Larvae collected in phytotelmata on Palawan, the Philippines, were bred and yielded three new species of genus Exochomoscirtes which are described. Exochomoscirtes pupae are described for the first time, and supplementary descriptions of larvae and females and some biological notes are provided. Scirtes (Curtoscirtes ?) brunneus sp. n. is named from a field-collected male. Larvae of unidentified species of Prionocyphon and Hydrocyphon are also recorded from Palawan. [ABSTRACT FROM PUBLISHER]

Hericia sanukiensis (Astigmata: Algophagidae) is a semi-aquatic mite inhabiting fermented sap flux of the Japanese sawtooth oak ( Quercus acutissima) and utilizes Nitidulidae (Coleoptera) as the dispersal (phoretic) carrier. Although nitidulid beetles are commonly found in sap flux, the occurrence of H. sanukiensis has been extremely limited to a few trees in Shikoku Island, Kagawa Prefecture, Japan. To elucidate the critical factors limiting the occurrence of this species, we compared several physical and biological characteristics of sap-exudation points, including the structure and temperature of tree trunks, period and abundance of sap exudation, and seasonal occurrence and dispersal behavior of nitidulid beetles between environments with and without mites. During the two consecutive years of field research, we found that only sap-exudation points with obvious tree holes (ringent area >10 cm, depth >10 cm) had sustained mite populations throughout the observation period. In contrast, for the sap-exudation points lacking tree holes, H. sanukiensis temporally (from spring to autumn) colonized only when the sap production was considerably high. Thus, we suggest that the settlement of H. sanukiensis populations requires tree holes as an overwintering habitat. Nitidulid beetles also concentrated in areas with high sap production and did not disperse from such habitats during the sap flow season. This indicates that H. sanukiensis mites may only disperse and colonize new habitats at very limited opportunities, such as drastic habitat deterioration, which may promote the movement of their carrier. Taken together, these findings may explain the limited occurrence of this mite species. [ABSTRACT FROM AUTHOR]

The bromeliad habitat contributes to a high biodiversity and we recorded three treefrog species as new phoretic agents of ostracods, and a first case of hyperphoresy among treefrogs, ostracods and ciliates, in these habitats of Atlantic Forest. Densities of ciliates and ostracods showed significant relationships suggesting the importance of hyperphoresy for ciliate dispersion. [ABSTRACT FROM AUTHOR]

Parental care is a common strategy among vertebrates to ensure successful reproduction. Anuran amphibians have evolved a remarkable diversity of reproductive methods including advanced levels of parental care. Among the most derived strategies are those of the Neotropical poison frogs (Dendrobatidae). These amphibians exhibit a wide array of behavioural traits such as egg guarding, larval transport by parental frogs and larval feeding with trophic (unfertilized) eggs. Ranitomeya variabilis from the upper Amazon basin in Peru deposits both eggs and tadpoles in phytotelmata. The exploitation of these small pools is advantageous as it lowers the risk of predation, but it is more costly because of limited resource availability. Additionally, poison frog larvae are often cannibalistic, so the identification and avoidance of conspecifics represents an adaptive behaviour for these amphibians. While studies have shown that poison frogs actively avoid depositing with conspecifics, the mechanism for assessing pool quality remains unknown. In field experiments, we found that parental R. variabilis frogs used chemical cues to recognize the presence of tadpoles in phytotelmata. Furthermore, they distinguished between cannibalistic and noncannibalistic tadpoles, a behaviour that supports the survival of their own offspring. [Copyright &y& Elsevier]

Many species of bromeliads create an aquatic microcosm among their leaves. Besides their native aquatic fauna, these microcosms can be used by larvae of invasive mosquitoes like Aedes aegypti. We compared the mortality among A. aegypti larvae placed inside tanks of Aechmea fasciata bromeliads with larvae placed inside artificial microcosms and with microcosms with low pH (5.4), which simulate the acidic conditions found inside bromeliad tanks. A. aegypti larvae suffered a significantly higher mortality inside bromeliad tanks compared to larvae in control microcosms, but the mortality inside bromeliads did not differ statistically from that found in artificial microcosms simulating bromeliad acidic conditions. We concluded that bromeliad tanks tend to be a less suitable environment for the development of A. aegypti larvae than artificial containers due to the acidification generated by bromeliad physiology. [ABSTRACT FROM AUTHOR]

Background Carnivorous pitcher plants (CPPs) use cone-shaped leaves to trap animals for nutrient supply but are not able to kill all intruders of their traps. Numerous species, ranging from bacteria to vertrebrates, survive and propagate in the otherwise deadly traps. This paper reviews the literature on phytotelmata of CPPs. Pitcher Fluid as a Habitat The volumes of pitchers range from 0·2 mL to 1·5 L. In Nepenthes and Cephalotus, the fluid is secreted by the trap; the other genera collect rain water. The fluid is usually acidic, rich in O2 and contains digestive enzymes. In some taxa, toxins or detergents are found, or the fluid is extremely viscous. In Heliamphora or Sarracenia, the fluid differs little from pure water. Inquiline Diversity Pitcher inquilines comprise bacteria, protozoa, algae, fungi, rotifers, crustaceans, arachnids, insects and amphibia. The dominant groups are protists and Dipteran larvae. The various species of CPPs host different sets of inquilines. Sarracenia purpurea hosts up to 165 species of inquilines, followed by Nepenthes ampullaria with 59 species, compared with only three species from Brocchinia reducta. Reasons for these differences include size, the life span of the pitcher as well as its fluid. Mutualistic Activities Inquilines closely interact with their host. Some live as parasites, but the vast majority are mutualists. Beneficial activities include secretion of enzymes, feeding on the plant's prey and successive excretion of inorganic nutrients, mechanical break up of the prey, removal of excessive prey and assimilation of atmospheric N2. Conclusions There is strong evidence that CPPs influence their phytotelm. Two strategies can be distinguished: (1) Nepenthes and Cephalotus produce acidic, toxic or digestive fluids and host a limited diversity of inquilines. (2) Genera without efficient enzymes such as Sarracenia or Heliamphora host diverse organisms and depend to a large extent on their symbionts for prey utilization. [ABSTRACT FROM AUTHOR]

The poison frog Ranitomeya reticulata was studied for 3 months while mark-recapture surveys were performed. Ranitomeya species deposit terrestrial clutches and carry tadpoles to phytotelmata with few taxa performing biparental brood care including larval feeding. Home range size and spatial affinity to phytotelmata in the genus are linked to mating systems. In R. reticulata, individual home range size and overlap were similar in both sexes, indicating equal levels of site fidelity. Although territory defence was never observed, strong intrasexual intolerance within individuals' core areas was found. The large intersexual home range overlap for breeding pairs indicated that mate fidelity occurs. Individuals' home ranges were not overlapping, suggesting that R. reticulata lacks pair-bonding or strongly cooperative behaviour in parental duties. The number of ground bromeliads containing phytotelmata and home range size of males were positively correlated. Our findings suggest that females do not perform egg-feeding and male-only parental care is likely. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Biociencias is the property of Revista Brasileira de Biociencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The physical and chemical characteristics of pitcher plant leaf fluid, orphytotelm, influence the phytotelm inhabitants, which in turn affect plant fitness. Phytotelm conditions vary between seasons yet few studies sample in multiple seasons or during the winter in portions of the plant's range where winter freezing normally occurs. Phytotelm conditions were characterized in two populations of Sarracenia purpurea L. in Jackson Bog State Nature Preserve, Jackson Township, Stark County, OH. Twenty leaves were arbitrarily sampled from each population once every ten days from November 2008 to September 2009. Phytotelm characteristics were compared between populations and with bog water adjacent to each population. Temperatures significantly differed between seasons, between pitcher plant populations and between the phytotelm and adjacent bog water, pH significantly differed between seasons and between pitcher plant populations, but not between the phytotelm and the adjacent bog water. Phytotelm volume and the number of frozen and dry leaves differed between populations. Results suggest that the presence and duration of non-frozen fluid could be an important source of selection on phytotelm inhabitants. Differences in phytotelm conditions between populations suggest that sampling regimes in sites with multiple populations or one very large population should account for microhabitat variations. [ABSTRACT FROM AUTHOR]

The fourth instar larva and pupa of Forcipomyia (Phytohelea) bromelicola (Lutz) are redescribed and illustrated, and compared with immatures of F. (P.) musae Clastrier and Delecolle and F. (P.) dominicana de Meillon and Wirth. Both life stages were photographed using scanning electron microscopy and phase-contrast light microscopy. The immatures were collected from bromeliads in Florida, USA. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine how phytotelm communities differ in four Eryngium sp. of different morphologies. Macro-invertebrate communities from 320 individual plants of Eryngium horridum, E. stenophyllum, E. serra, and E. elegans were sampled in Buenos Aires Province, Argentina. The morphology and structure of each Eryngium specimen, and water volume and debris in their phytotelmata, were measured. Morphology indicated that E. elegans and E. serra are closely related and differ from E. horridum and E. stenophyllum. The latter two species are markedly different from E. stenophyllum, the biggest of the four. The communities differed among these Eryngium species, but a large number of generalist macro-invertebrates use all four phytotelmata. Canonical correlation analysis showed that diptera are inhabitants in E. horridum, and micro-crustaceans in E. serra and E. elgans. By contrast, no specific taxa were grouped in E. stenophyllum. Results of inter-specific association ( C8 coefficient) show that species of Culicidae and Chironomidae are highly positive associations in E. horridum, by contrast with the negative association observed in E. stenophyllum. Culex renatoi (Culicidae) and Polypedilum sp. (Chironomidae) were highly likely to co-occur in the same plant of E. serra, but not with Metriocnemus eryngiotelmatus (Chironomidae). Larsia sp. (Chironomidae) was the species better associated with the other macro-invertebrates in E. elegans. The food web was constructed from Eryngium phytotelmata. This study includes an updated list of known aquatic and semi-aquatic invertebrates reported from Eryngium phytotelmata, and their bibliography. [ABSTRACT FROM AUTHOR]

The article presents a study on the neotropical poison frogs Ranitomeya (R.) imitator and R. fantastica, to determine whether there more than one mode of breeding resource between the two species. It states that R. imitator and R. variabilis coexist through functional resource partitioning and niche segregation and avoid competition against each other through specialization. The study, which was conducted at a forest in San Martin, Peru from July 22 to November 17, 2008, involves the use of 125 artificial phytotelmata with 500 milliliters (ml) of water that were attached to 25 trees in the study site. The result shows that niche partitioning, such as the size of breeding pools, could be a sufficient niche differentiation to avoid competition between the R. imitator and R. fantastica.

With the growing interest in small aquatic water bodies, especially as naturally replicated model systems for ecological research, aquatic invertebrate communities in phytotelmata are increasingly receiving attention these days. The recognition of the substantial contribution to the regional species pool of specialised species draws further attention to these small and often temporary habitats. The methods currently used for studying communities in some types of phytotelma, such as bromeliads, tend to be destructive, typically involving complete dissection of the plant. The expected increase in sampling intensity associated with the increasing interest in phytotelmata may result in a negative impact on plant populations in some areas, decreasing numbers in an unsustainable way, especially in locations with ongoing, intensive research. We therefore aimed to investigate whether less-destructive sampling methods can achieve sufficient data quality to allow their use as alternatives to complete plant dissection. We tested the effectiveness of three such methods in measuring the aquatic invertebrate communities in tank bromeliads ( Tillandsia guatemalensis) in Cusuco National Park, Honduras. The three methods were pipetting the water out of the bromeliad, turning the bromeliad upside down and dissecting only the outer part of the plant (the oldest, often deteriorating leaves). Overall, we found that these methods were poor predictors of richness and abundance of the organisms in communities. However, we found big differences between taxonomic groups, depending in part on the ecology of the organisms, and we suggest that some less-destructive alternative methods may be appropriate for studying some specific groups (e.g. Culicidae). Based on these results and a rapid survey of the abundance of bromeliads in the national park, we question whether intensive, ongoing research into aquatic invertebrate communities in similar phytotelma populations is sustainable. From the point of view of conservation, alternative model systems need to be found. [ABSTRACT FROM AUTHOR]

Water-filled treeholes are in reality tiny ponds in the woodland ecosystem and provide a unique habitat for a number of different organisms that make up the treehole community. The community is a detritus based system that relies primarily on decomposing leaves from the autumn leaf drop as an energy source. Among the arthropod inquilines is a histiostomatid mite, Hormosianoetus mallotae (Fashing), an obligate inhabitant that filters microorganisms and other organic matter from the fluid. Dispersal is accomplished by a heteromorphic deutonymphal stage (= hypopus). While larvae, protonymphs, tritonymphs and adults are found in the treeholes throughout the year, deutonymphs are present only in May and June when conditions are optimal for population growth by the treehole residents. Deutonymphs therefore do not form in response to adverse conditions, but rather to serve purely as dispersal agents for colonizing new treeholes and for out-crossing among populations. Deutonymphs are phoretic on adults of Mallota bautias (Walker) and M. posticata (Fabricius) (Diptera: Syrphidae), the larvae of which are also obligate treehole inhabitants. Mallota sp. have a one year life cycle with the adult stage also present only during May and June. Hormosianoetus mallotae is arrhenotokous and disperses only as female deutonymphs, propagules mating with the haploid male offspring of the dispersants. Females are ovoviviparous, retaining eggs in the reproductive system during embryonic development and giving birth to fully formed larvae. Development from egg to adult is approximately 14 days for males and 20 days for females. Like other mite inhabitants of the treehole community, H. mallotae is a K-selected species. [ABSTRACT FROM AUTHOR]

1. The macrofauna living inside the phytotelmata or on the foliage of bromeliads could be directly affected by habitat and seasonality. Habitat may also have indirect effects by affecting plant morphology. 2. In Chaco forests, a facultative epiphytic bromeliad ( Aechmea distichantha) shows different morphology when growing in sun and shade conditions. Therefore, the abundance and assemblage composition of the macrofauna living on this bromeliad were analysed in different habitats and seasons. 3. Sun plants were shorter, had higher tank water content, but lower litter mass than shade ones. Phytotelmata water temperature and pH were similar between habitats. 4. In the phytotelmata, the macrofauna abundance and richness per plant, as well as total richness, were similar between habitats and among seasons. Detritivores were more abundant than predators in all habitats and seasons. Shade plants had a higher proportion of detritivores than sun plants in spring and summer, but not in winter. 5. On the bromeliad foliage, the macrofauna abundance and richness per plant were lower in winter. There were no differences in abundance between habitats, but shade plants had higher species richness than sun plants. In spring and summer, total richness was higher in shade plants than in sun plants. In spring and summer, detritivores were more abundant for shade, whereas ants were more abundant in sun plants. The proportion of hunting spiders was higher in the shade in spring and summer. 6. Our study showed that habitat mainly affects bromeliad-foliage macrofauna, but not the phytotelmata macrofauna. [ABSTRACT FROM AUTHOR]

The main theories explaining the biological diversity of rain forests often confer a limited understanding of the contribution of interspecific interactions to the observed patterns. We show how two-species mutualisms can affect much larger segments of the invertebrate community in tropical rain forests. Aechmea mertensii (Bromeliaceae) is both a phytotelm (plant-held water) and an ant-garden epiphyte. We studied the influence of its associated ant species (Pachycondyla goeldii and Camponotus femoratus) on the physical characteristics of the plants, and, subsequently, on the diversity of the invertebrate communities that inhabit their tanks. As dispersal agents for the bromeliads, P. goeldii and C. femoratus influence the shape and size of the bromeliad by determining the location of the seedling, from exposed to partially shaded areas. By coexisting on a local scale, the two ant species generate a gradient of habitat conditions in terms of available resources (space and food) for aquatic invertebrates, the diversity of the invertebrate communities increasing with greater volumes of water and fine detritus. Two-species mutualisms are widespread in nature, but their influence on the diversity of entire communities remains largely unexplored. Because macroinvertebrates constitute an important part of animal production in all ecosystem types, further investigations should address the functional implications of such indirect effects. [ABSTRACT FROM AUTHOR]

Data on population dynamics and distribution are of primary interest to biologists because they reveal information about the species' ecology and evolution and are thus essential for conservation efforts. Patchily distributed species are especially interesting for conservation studies, because of their sometimes very specific environmental requirements. An example of a highly specialised species is the leaf litter frog Phrynobatrachus guineensis. This small species (<20 mm) is short lived, presumably weakly mobile and highly specialised because it uses tree-holes and other small water-filled cavities with very particular abiotic and biotic characteristics for breeding. Previous field studies revealed that P. guineensis exhibited a clumped distribution in Tai National Park (TNP), Ivory Coast, suggesting that the park's population might be subdivided into several (sub)populations. We therefore investigated the population genetic structure of the park using four microsatellite loci, which are the first described microsatellite markers for any African anuran in general and for a species of the family Phrynobatrachidae in particular. In contrast to our expectations, we detected only a slightly significant genetic differentiation based on allele frequencies. We found no correlation between the geographic and genetic distances (isolation by distance) and Bayesian clustering revealed no genetic substructure. We did, however, detect small but significant genetic differentiation between subsequent seasons. The most probable explanation for the lack of population structure is that P. guineensis is more mobile than expected. Adults, most likely females but possibly also juveniles, are able to traverse matrix habitats in which no breeding activities were detected. The temporal genetic differentiation may be the consequence of genetic drift due to high mortality rates and/or non-random mating. Both explanations would be consistent with our field data. [ABSTRACT FROM AUTHOR]

1. Ecological theory has focused on negative interactions, such as competition and predation, to explain species' effects on one another. This study demonstrates the importance of considering both positive and negative interactions in explaining how species influence abundances at the local scale. 2. Two experiments were conducted using the aquatic insect food web in Costa Rican bromeliad phytotelmata. Manipulations contrasted the strength of predation between trophic levels versus facilitation within a trophic level on the emergence of detritivore chironomids. 3. Predation had a strong negative effect on chironomids, reducing emergences by 81% overall. Most predation was as a result of the top predator, the odonate Mecistogaster modesta; the intermediate predator, a tanypodine chironomid, had little effect. In the absence of predators, shredder and scraper detritivores (tipulid and scirtid larvae) increased the emergence rate of chironomid larvae by 86%. The mechanism of facilitation was likely the processing, by tipulids and scirtids, of intact detritus into fine particles that the detritivore chironomids consume or use to build protective cases. 4. This study is among the first demonstrations of a processing chain in a multi-species context, and in bromeliad-insect food webs. Our finding that top-down effects are of similar magnitude to facilitative effects suggests that the relative importance of processing chains in nature will depend on food web context. [ABSTRACT FROM AUTHOR]

Hericia sanukiensis (Acari, Algophagidae) is a species of tree sap mite which has been newly discovered in the sap flux of oak trees (Quercus acutissima). In this study, we have clarified the life history of H. sanukiensis at the onset of sap exudation in spring, overwintering deutonymphs molt to tritonymphs as their molting is exacerbated by the sugar contained in the tree sap, and develop to adulthood and reproduce. The mite colony develops as long as the sap continues to exude during the spring and summer. In this period, most of the protonymphs develop into tritonymphs directly bypassing the deutonymphal stage completely. Facultative deutonymphs which arise in the summer season are phoretic morphs. They attach to coleopteran insects, especially of the family Nitidulidae, as carriers by which to disperse. In autumn (when sap exudation terminates), most of the protonymphs molt to non-phoretic deutonymphs. In winter (without sap exudation), the mite colony is composed only of non-phoretic deutonymphs. [ABSTRACT FROM AUTHOR]

Evaluating the factors that regulate bacterial growth in natural ecosystems is a major goal of modern microbial ecology. Phytotelm bromeliads have been used as model ecosystems in aquatic ecology as they provide many independent replicates in a small area and often encompass a wide range of limnological conditions. However, as far as we know, there has been no attempt to evaluate the main regulatory factors of bacterial growth in these aquatic ecosystems. Here, we used field surveys to evaluate the main bottom-up factors that regulate bacterial growth in the accumulated water of tank bromeliads. Bacterial production, water temperature, water color, chlorophyll-a, and nutrient concentrations were determined for 147 different tank bromeliads in two different samplings. Bromeliad position and the season of sampling were also noted. Bacterial production was explained by ion ammonium concentration and water temperature, but the total variance explained was low ( r2 = 0.104). Sampling period and bromeliad position were included in additional models that gave empirical support for predicting bacterial production. Bromeliad water tanks are extremely variable aquatic ecosystems in space (among bromeliads) and time (environmental conditions can change within hours), and it is well known that bacterial production responds rapidly to environmental change. Therefore, we concluded that several factors could independently regulate bacterial growth in phytotelm bromeliads depending on the characteristics of each bromeliad, such as location, amount of detritus, and ambient nutrient concentrations. A clear bottom-up limitation pattern of bacterial production in tropical phytotelm bromeliads was not found. [ABSTRACT FROM AUTHOR]

Tank bromeliads harbour aquatic microcosms with many endemic species among their leaves. We performed a set of experiments to determine which factors maintain the bromeliad aquatic fauna in isolation from neighbouring ponds. We cultivated three invertebrates species (an ostracod, an annelid and a cladoceran) from a pond surrounded by terrestrial bromeliads in Southeastern Brazil and introduced them inside cleaned bromeliads, using recipients with the same volume as controls. The pH, conductivity and organism densities were monitored in the bromeliad samples and controls for 41 days. The samples introduced inside the cleaned bromeliads showed a significant decrease in pH and conductivity compared to the controls. The pond organism populations introduced in the bromeliads presented a high extinction rate and a significant population decrease when compared to the ones introduced in the controls. We attributed the population decline experienced by the pond organisms to the oligotrophic conditions generated inside the tanks by the bromeliads due to the nutrient absorption. We suggest that the changes in water chemistry induced by the bromeliads could play an important role in isolating their microcosm communities from other freshwater systems. Other mechanisms that could produce the high rates of endemism in bromeliad fauna are discussed. [ABSTRACT FROM AUTHOR]

Human activities have been causing dramatic and unprecedented changes to the Earth’s ecosystems, and are a primary factor associated with biological invasions. Disturbed and fragmented habitats allow some vector mosquitoes to thrive. The New Zealand landscape has been extensively modified since the arrival of humans, and there is accumulating evidence that the distribution of mosquitoes is being altered as a result of anthropogenic environmental changes. This study aimed to assess whether forest habitat size affected the community composition of mosquitoes, and whether the density of the introduced brushtail possum would benefit exotic mosquito species that feed primarily on mammal hosts. Extensive sampling of the mosquito community was carried out using dry ice-baited light traps, oviposition traps, and larval surveys. The results provided the first experimental evidence in New Zealand that changes in forest habitat size affect the indigenous and introduced mosquito fauna differently. The proportion of native species making up the mosquito community appears to be steadily reduced as native forest habitats become smaller. In contrast, the opposite pattern appears to occur for the introduced vector Aedes notoscriptus. Although there was a trend indicating that possums may have a negative impact on a native species ( Culex pervigilans), the impact of these animals on the mosquito fauna remains unclear. The evidence suggests that the conservation of large pristine forest ecosystems in New Zealand could have human health implications. [ABSTRACT FROM AUTHOR]

GIS assumes an increasingly prominent role in niche modelling, particularly for those applications that either predict a species'' niche or estimate the environmental factors that determine a species'' distribution. The use of GIS to model population-level distributions has received considerably less attention. We developed a Monte Carlo method designed to test for statistical associations between population distribution and different types of spatial data. This method examines the spatial distribution between species presence points and distance to key vegetation, comparing the association for the observed data to that of a random data set. Poison frogs (genus Dendrobates) display a diverse array of complex parental care strategies, which are linked by an elaborate network of interactions between ecological and social factors. Territorial species vary significantly in their associated reproductive strategies, reproductive resources and size. Species with higher levels of cooperation in parental care have been hypothesized to be more strongly territorial. Here we investigate differences in spatial use patterns between two species of poison frogs, D. imitator and D. variabilis, that differ in parental care type (uniparental male care versus biparental care, respectively). We predicted that: (1) D. imitator would be more closely associated with phytotelmata than would D. variabilis; (2) home ranges of D. imitator pairs would be more inclusive and overlap more than those of D. variabilis pairs; (3) D. imitator pairs would maintain smaller home ranges than D. variabilis pairs; (4) D. imitator pairs would maintain spatially exclusive home ranges. Our results strongly support the prediction that differences in parental care of these two species are reflected in their spatial habitat use, particularly with regard to pool fidelity, territoriality, and home range size and overlap. [Copyright &y& Elsevier]

Abstract: Tank-bromeliads are discrete habitats which contain distinct aquatic communities, and which commonly occur in the neotropics. Because they span a broad range of ecological gradients in terms of habitat structure and amount of resources, researchers study the associations between the biodiversity of communities and these gradients in rainforests, where the very high species richness and densities within other continuous habitats makes it difficult to quantify animal communities. We analysed the diversity of aquatic insect communities in relation to different tank-bromeliad species in a primary rainforest (French Guiana) using artificial intelligence and complex optimization techniques to classify communities and model their determinants. First, the self-organizing map (neural network) was used to classify 158 bromeliads according to the quantitative structure of the insect communities. Catopsis berteroniana and Guzmania lingulata formed separate clusters of plants on the virtual map, while Vriesea splendens, Vriesea pleiosticha and Aechmea melinonii were grouped together in the remaining clusters. Some insect taxa occurred in all bromeliads, while other taxa were specific to a given species. Second, general linear modelling allowed us to specify the influence of the bromeliad species; water volume and volume of fine particulate organic matter inside of the tank; elevation above the ground; and sampling site on taxonomic richness and insect abundance. The number of taxa and individuals per plant increased with greater water volume, but the slope of the relationships depended on the bromeliad species. The significant influence of bromeliad species suggested that at similar water volumes different plant species had different taxon richness and insect abundance. Greater amounts of fine particulate organic matter were detrimental to community diversity in the tanks, probably because they decreased available space by clogging it and/or affected oxygen concentrations. The influence of tank-bromeliad species on the aquatic insect community was primarily related to their physical (and probably chemical) features rather than to species-specific associations sensu stricto. The classification of bromeliads with respect to animal species is likely to provide referential schemes for those biodiversity patterns to be expected under certain conditions, and may help to target model communities for subsequent experimental research. [Copyright &y& Elsevier]

Several aspects of the reproductive behaviour of species of the Scinax perpusillus group (S. perpusillus, S. v-signatus, S. littoreus, and three other not yet described species) obtained from direct field observations and nocturnal video filming are presented and evaluated. Males of the observed species have behavioural characters, including aspects of their call, that are indicative of territory defence. Vocalizations are elaborate and represent intra- and inter-sexual communication mechanisms. Females present behaviour relating to the inspection of egg-laying sites (bromeliad leaf-tanks), reduced and partitioned clutch. This set of behaviours is not only indicative of a sophisticated control mechanism over egg laying and spermatozoid release, but also of the existence of a behavioural repertoire that probably originated in the ancestor of these species and could be considered a synapomorphy for this group of species. Furthermore, the behaviours described herein comprise a new reproductive strategy for frogs that reproduce in bromeliads. [ABSTRACT FROM AUTHOR]

Tree-holes provide an important microhabitat that is used for feeding, roosting and breeding by numerous species around the world. Yet despite their ecological importance for many of New Zealand's endangered species, few studies have investigated the abundance or distribution of tree-holes in native forests. We used complementary ground and climbed tree surveys to determine the abundance, distribution and characteristics of tree-holes in undisturbed Nothofagus forest in the Lewis Pass, New Zealand. We found that hole-bearing trees were surprisingly abundant compared with many other studies, including Australian Eucalyptus species and American beech. In fact, we estimated as many as 3906 tree-holes per hectare, of which 963 holes per hectare were potentially large enough to provide roost sites for hole-nesting bats in New Zealand, while only eight holes per hectare were potentially suitable for specialist hole-nesting birds. This was of great interest as primary cavity-excavating animals are absent from New Zealand forests, compared with North America and Australia. Moreover, tree-hole formation in New Zealand is likely to be dominated by abiotic processes, such as branch breakage from windstorms and snow damage. As has been found in many other studies, tree-holes were not uniformly distributed throughout the forest. Tree-holes were significantly more abundant on the least abundant tree species, Nothofagus fusca, than on either N. menziesii or N. solandri. In addition to tree species, tree size was also an important factor influencing the structural characteristics of tree-holes and their abundance in this forest. Moreover, these trends were not fully evident without climbed tree surveys. Our results revealed that ground-based surveys consistently underestimated the number of tree-holes present on Nothofagus trees, and illustrate the importance of using climbed inspections where possible in tree-hole surveys. We compare our results with other studies overseas and discuss how these are linked to the biotic and abiotic processes involved in tree-hole formation. We consider the potential implications of our findings for New Zealand's hole-dwelling fauna and how stand dynamics and past and future forest management practices will influence the structural characteristics of tree-holes and their abundance in remnant forest throughout New Zealand. [ABSTRACT FROM AUTHOR]

Time- and context-dependent nest site selection of a phytotelm-breeding frog (Kurixalus eiffingeri) was evaluated in a natural bamboo habitat in subtropical Taiwan from 2004 to 2005. At the beginning of the breeding season (mid-March), frogs preferred bamboo stumps with large water holding capacity, which may be considered high-quality stumps since water availability is critical to the survival of tadpoles. Prior to 21 May, no tadpole-occupied stumps were re-used even though they represented 10--40% of total stumps at the study site; however, tadpole-occupied stumps were consistently re-used afterwards. Stumps with fewer tadpoles were used proportionally more than those with more tadpoles. By choosing the stumps with fewer tadpoles, the negative competitive effect of the late-clutch tadpoles on the early-clutch tadpoles would be somewhat alleviated. Male frogs did not breed in the same bamboo stump for consecutive breeding events, which may relate to the male reproductive strategy. We propose that it would often be a better strategy for a male frog to breed in different stumps than to stay in the same stump, even if the stump was of high quality. Breeding in multiple stumps would increase the number of breeding opportunities by reducing the interval between successive mating attempts, minimize the inter-clutch competition between tadpoles, and avoid competition between two cohorts of its own genetically-related tadpoles. Our results suggest that stump quality is indicated by water holding capacity and the number of the tadpoles in the stump during early and late breeding seasons. Thus, oviposition site choice in this species is dependent on stump quality, but stump quality is both context- and time-dependent. [ABSTRACT FROM AUTHOR]

Ecologists have hypothesized that the exponent of species- area power functions (z value) should increase with trophic level. The main explanation for this pattern has been that specialist predators require prior colonization of a patch by their prey, resulting in a compounding of the effects of area up trophic levels. We propose two novel explanations, neither of which assumes trophic coupling between species. First, sampling effects can result in different z values if the abundances of species differ (in mean or evenness) between trophic levels. Second, when body size increases between trophic levels, effects of body size on z values may appear as differences between trophic levels. We test these alternative explanations using invertebrate food webs in 280 bromeliads from three countries. The z value of predators was higher than that of prey. Much of the difference in z values could be explained by sampling effects but not by body size effects. When damselflies occurred in the species pool, predator z values were even higher than predicted, as damselflies avoid small, drought-prone bromeliads. In one habitat, dwarf forests, detrital biomass became decoupled from bromeliad size, which also caused large trophic differences in z values. We argue that there are often simpler explanations than trophic coupling to explain differences in z values between trophic levels. [ABSTRACT FROM AUTHOR]

Factors contributing to the evolution of reproductive strategies have been of great interest to evolutionary biologists. In tropical amphibians predation and competition have been suggested to play a major role. Poison frogs of the family Dendrobatidae display a trend towards the use of very small pools and increased parental care, particularly in the genus Dendrobates. Some species with female parental care, asymmetrical biparental care and biparental care, have evolved novel behaviors in association with the use very small phytotelmata. It has been hypothesized that selection pressure imposed by predation and competition favored the use of small phytotelmata, and this, in turn, produced selection for trophic egg provisioning to ameliorate the lack of available nutrients. To elucidate the ecological factors associated with the transition from uniparental male care to biparental care and associated changes in social behaviors, we evaluated key behavioral and ecological differences between Dendrobates imitator and D. variabilis. Dendrobates imitator used significantly smaller phytotelmata in different plant species than D. variabilis for tadpole and embryo deposition. The parental strategy of D. variabilis was limited to male parental care, whereas D. imitator exhibited biparental care. Males and females of D. variabilis were observed to have a promiscuous mating system with little mate fidelity. This contrasted with D. imitator, where paired males and females were observed interacting daily and were never observed courting additional mates. Our results are consistent with the hypothesis that a key ecological difference between these species, involving the size of pools typically used for reproduction, is strongly associated with the evolution of biparental care and monogamy in D. imitator. [ABSTRACT FROM AUTHOR]

The article discusses a study which aimed to describe the ultimate stadium larva of Bromeliagrion rehni, to provide bionomic information about the species and to describe its association with the phytotelm of Guzmania brasiliensis Ule in the Amazon region of Brazil. The study was conducted in the Reserva Florestal Adolpho Ducke, located near Manaus and the twelve samplings were done between April, 2003 and April, 2005. Findings suggest that larvae were most abundant in the rainy season and water volume was positively related to the abundance of B. rehni.

Bromeliads are a Neotropical plant family (Bromeliaceae) with about 2,900 described species. They vary considerably in architecture. Many impound water in their inner leaf axils to form phytotelmata (plant pools), providing habitat for terrestrial arthropods with aquatic larvae, while their outer axils provide terraria for an assemblage of fully terrestrial arthropods. Many bromeliads are epiphytic. Dominant terrestrial arthropods with aquatic larvae inhabiting bromeliad phytotelmata are typically larvae of Diptera, of which at least 16 families have been reported, but in some circumstances are Coleoptera, of which only three families have been reported. Other groups include crabs and the insect orders Odonata, Plecoptera, and Trichoptera, plus Hemiptera with adults active on the water surface. The hundreds of arthropod species are detritivores or predators and do not harm their host plants. Many of them are specialists to this habitat. Terrestrial arthropods with terrestrial larvae inhabiting bromeliad terraria include many more arachnid and insect orders, but relatively few specialists to this habitat. They, too, are detritivores or predators. Arthropod herbivores, especially Curculionidae (Coleoptera) and Lepidoptera, consume leaves, stems, flowers, pollen, and roots of bromeliads. Some herbivores consume nectar, and some of these and other arthropods provide pollination and even seed-dispersal. Ants have complex relationships with bromeliads, a few being herbivores, some guarding the plants from herbivory, and some merely nesting in bromeliad terraria. A few serve as food for carnivorous bromeliads, which also consume other terrestrial insects. Bromeliads are visited by far more species of arthropods than breed in them. This is especially notable during dry seasons, when bromeliads provide moist refugia. [ABSTRACT FROM AUTHOR]

The aim of this research was to evaluate the effect of temperature on the development time and survival of Culex (Culex) hepperi Casal and Garcia, 1967. Individuals were reared in the laboratory, from the first larval stage to adult emergence, at five constant temperatures: 15, 20, 25, 30, and 33°C. The total development time was inversely related to temperature between 15 and 25°C. No differences were observed in the development time between sexes and no adults emerged at 33°C. In the larval stages III and IV, the time required for molting to the next stage increased at 30°C. The highest survival was recorded at 20°C. The more developed stages were less resistant to temperatures above and below 20°C. According to the nonlinear model of Briére, the lower and upper development thresholds were 2.6 and 33°C, respectively. Our results suggest that the effect of temperature depends upon the stage of development of C. hepperi [ABSTRACT FROM AUTHOR]

Bamboo stumps can be a congenial breeding habitat of the mosquitoes. In view of this, a preliminary assessment of the dipteran immatures inhabiting the stumps of bamboo groves in the Darjeeling Himalayas was carried out at a spatial scale. Of the 104 stumps of Dendrocalamus hamiltoni surveyed, 70 were found to host immatures of three dipteran species, the mosquitoes Aedes aegypti and Culex quinquefasciatus and the midges Chironomus sp. in varying densities. Though the stumps varied in diameter, in each stump on average 12. 1 immatures were found. The abundance of the immatures was positively correlated with the diameter of the stumps ( r=+0.382; P < 0.001) but negatively with the pH of the water present in the stumps ( r=–0.336; P < 0.01). The coefficient of association was found to be +8.4 for the Ae. aegypti and Chironomus immatures, while in the rest of the species pair the association seemed to be independent. Thus it can be concluded that the stumps in the bamboo groves of Darjeeling Himalayas provides a favourable habitat for the mosquito and chironomid immatures. [ABSTRACT FROM AUTHOR]

Harpellales (Zygomycota: Trichomycetes) fungi are cosmopolitan obligate inhabitants of the gut of immature insects. A biweekly survey of gut fungi associated with chironomid (Chironomidae: Diptera) larvae living in the impounded water from Eryngium cabrerae (Apiaceae) phytotelmata from Punta Lara forest, Argentina, was done Jan 2003-Dec 2004. Two species of Harpellales were associated with chironomid larvae, Smittium phytotelmatum in the hindgut of Polypedilum sp. and Stachylina lentica in the midgut of both Polypedilum sp. and Metriocnemus eryngiotelmatus. No statistically significant differences were recorded in the prevalence of these Harpellales between seasons. Environmental variables (temperature, rainfall and relative humidity), impounded water volume, pH and chironomid larval density did not have an effect on the prevalence of the Trichomycetes. [ABSTRACT FROM AUTHOR]

(1) A study of the metazoan community occurring in water-filled tree-holes in southern Germany has been performed to determine the relationships among the key species of arthropods found within the community and a range of structural, physical and chemical factors, using multivariate techniques. (2) Four animal species were sufficiently common to allow identification of the preferred environments for their larvae. The aedine mosquito, Aedes geniculatus, prefers shallow open tree-holes with relatively little leaf litter even though these may represent less permanent water-bodies. The scirtid beetle, Prionocyhon serricornis, occurs in larger, deeper holes with greater amounts of leaf litter and a more predictable aquatic environment, although open water is not a requisite. Larvae of the orthocladiine chironomid, Metriocnemus cavicola, favours shallow more open tree-holes with higher litter content but with sufficient open water to ensure an adequate oxygen supply. The eristaline syrphid, Myatropa florea, favours shallow, open tree-holes with low litter content. (3) There is no evidence that interspecific interactions affect the distribution or abundance of any of these species. (4) The autecological results are discussed in light of those available for phytotelm dwellers elsewhere. The food-web overall may be interpreted as so simple that it is driven by ‘bottom-up’ environmental factors with no part played by those community-level ‘top-down’ processes that may be adduced for more complex, multi-trophic level webs occurring elsewhere. No “processing chain commensalism” could be found in the arthropod community of the temperate German deciduous tree-hole dwellers. [ABSTRACT FROM AUTHOR]

1. Colonisation of ephemeral aquatic habitats via oviposition by invertebrates may be influenced by a variety of factors, such as the quality of aquatic habitat and the characteristics of the surrounding terrestrial environment. The water-holding bracts of Heliconia caribaea, a subtropical herb that produces ephemeral aquatic habitats, are colonised by a variety of aquatic invertebrates. To date, no experiments have been conducted to identify the cues that affect colonisation patterns via oviposition selection in Heliconia. 2. Artificial bracts were used to assess the influence of two types of resources found in bracts (plant produced carbohydrates and terrestrial snail faeces) on oviposition site-selection by invertebrate taxa via a replicated factorial design at four locations in the Luquillo Experimental Forest of Puerto Rico, U.S.A. Eleven microsite characteristics thought to affect oviposition were measured for each experimental container. 3. Most taxa responded in a minor way to microsite characteristics, whereas site selection by the most numerically dominant groups (e.g. Syrphidae) were influenced principally by resources within artificial bracts. Overall, the greatest response by particular taxa was to the presence of snail faeces. At the community level, total abundance, richness, and evenness of invertebrates increased with increasing biomass of faeces. Variation in sugar produced a more complex response. 4. In general, the terrestrial matrix surrounding these aquatic habitats was only a secondary determinant of population and community attributes; the principal factor affecting site selection was the quality of the aquatic habitat. [ABSTRACT FROM AUTHOR]

Water-filled treeholes are temporally and spatially variable habitats that consist of communities of a limited number of insect orders, namely dipterans and beetles. Since these systems are largely heterotrophic, treeholes are dependent on the surrounding terrestrial ecosystem for their basal energy input. In this study, we observed a cyclic succession of three system states in a water-filled Fagus grandifolia treehole: ‘connected’ during rainfall; ‘isolated’ during periods without rain; and ‘dry’ when no freestanding water was present. During the isolated phase, a rapid, microbially mediated turn-over of nitrogen and sulphate took place, coincident with an accumulation of orthophosphate. Ammonium was the dominant form of nitrogen in the treehole water, and a net decrease in its concentration was observed when the water volume decreased. Normally, nitrate concentration showed only minor fluctuations (0.3–1.3 mg l−1) and concentrations of nitrite were very low (3–18 μg l−1). Concentration of sulphate showed a net decrease, coincident with an increase in sulphide. During the connected phase, the effect of stemflow and throughfall on the nutrient concentrations in the treehole water proved to be variable. Over time, both dilution of, and increase in, treehole water nutrient concentrations were observed. Dissolved organic carbon (DOC) concentration showed a net decrease during the isolated phase. Spring coarse particulate organic matter input into the treehole was variable (0.20–1.74 mg cm−2 week−1). The observed variability in precipitation inputs as well as fall-in of organic matter underlines the pulsed character of basal energy entering the treehole food-web. DOC concentrations varied mainly with depth (15–57.4 mg l−1) as concentrations were almost three times greater within the detritus than within the water column. Bacterial abundances ranged from 7.3 × 105 to 9.3 × 106 cells ml−1 and did not appear to vary within the water column or in the detrital sediment. Rates of bacterial production increased 24 h after rain events, suggesting that the combined nutrient fluxes due to increased stemflow stimulate the microbial community. [ABSTRACT FROM AUTHOR]

Abstract: One group of mantellid frogs from Madagascar (subgenus Pandanusicola of Guibemantis) includes species that complete larval development in the water-filled leaf axils of rainforest plants. This group consists of six described species: G. albolineatus, G. bicalcaratus, G. flavobrunneus, G. liber, G. pulcher, and G. punctatus. We sequenced the 12S and 16S mitochondrial rRNA genes (∼1.8kb) from multiple specimens (35 total) of all six species to assess phylogenetic relationships within this group. All reconstructions strongly supported G. liber as part of the Pandanusicola clade, even though this species does not breed in plant leaf axils. This result confirms a striking reversal of reproductive specialization. However, all analyses also indicated that specimens assigned to G. liber include genetically distinct allopatric forms that do not form a monophyletic group. Most other taxa that were adequately sampled (G. bicalcaratus, G. flavobrunneus, and G. pulcher) likewise consist of several genetically distinct lineages that do not form monophyletic groups. These results suggest that many of the recognized species in this group are complexes of cryptic species. [Copyright &y& Elsevier]

Twenty-three species of Copestylum (Diptera, Syrphidae) were reared from Bolivia, Costa Rica, Ecuador, Mexico, and Trinidad from 1998 to 2004. Twenty-two were new species. We describe these new species, their breeding sites, and the third stage larva and/or the puparium of all 23 species. Adults had species-specific head shapes and colour patterns, but similarities between 14 of the species enabled two groups and three subgroups to be recognized. Nonetheless, the high level of morphological disparity suggests independent colonizations of bromeliads. Adult colour patterns appear to be predominantly cryptic in function and based on reflectiveness derived from matt to shiny integumental ground colours, combined with overlying areas of variously coloured hairs, dust, and pruinosity. In addition, disruptive spots, bands, and vittae occur on the face, thoracic pleurites, and second tergite. Larvae were saprophagous in either live or dead bromeliads with no overlap between categories. A major factor explaining variation in larval morphology could be access to food. Larvae in live bromeliads are characterized by varying levels of dorso-ventral flattening, and modifications to the mouthparts and prothorax. These features appear to facilitate feeding in the narrow spaces between overlapping bromeliad leaves. Larvae exploiting dead bromeliads are characterized by varying levels of armature to the thorax, and extensions to the anal segment. Armature either consists of arrangements of sclerotized spicules distributed at various places on the thorax or large hooks on the lateral margins. Armoured thoraces facilitate burrowing through decaying tissue, and extended anal segments may reduce exposure during respiration. © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society, 2007, 150, 267–317. [ABSTRACT FROM AUTHOR]

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The phoretic behaviour of ostracods ( Elpidium bromeliarum) andannelids ( Dero superterrenus) that inhabit tank bromeliads was studied. Our previous field observations had shown that bromeliad ostracods can be found attached to the skin of amphibians and reptiles that move among bromeliads, probably allowing the ostracods to colonise new tanks. In this paper, we present the first record of bromeliad annelids found attached to frogs moving among bromeliads in the field. We have also enlarged the database on bromeliad ostracods engaged in phoretic association with terrestrial vertebrates in three locations in southeastern Brazil. In our laboratory experiments bromeliad annelids show a strong significant tendency to climb onto papers that had been in contact with frog skin when compared with control papers, indicating a kind of chemically oriented behaviour. Bromeliad ostracods, on the other hand, attached themselves to treated and untreated papers with same frequency. When brought into contact with various species of frogs and lizards, the bromeliad annelids and ostracods both presented preference to attach themselves to frogs, but the annelids showed a stronger preference to attach to frogs and to avoid attachment to lizards. Another experiment demonstrated that bromeliad annelids are much more prone to dehydration than are ostracods. We suggest that the chemically oriented behaviour presented by bromeliad annelids toward frogs could diminish the risk of death by dehydration during the transport among bromeliads due to the moist characteristic of frog skins. [ABSTRACT FROM AUTHOR]

Ecological theory predicts that interspecific interactions can affect population and community dynamics. Two experiments were conducted on Mantidactylus bicalcaratus and M. punctatus, two sympatric frog species from Madagascar that live and breed in rain-forest plants (Pandanus spp.), to test for interspecific competition. The first experiment examined larval growth rates and survivorship with and without conspecifics. While survivorship did not differ among treatments, mean growth rates for M. bicalcaratus were significantly reduced in the presence of M. punctatus larvae. The second experiment manipulated the presence and density of adults in Pandanus plants. Emigration from and immigration to experimental plants tended to be higher and lower, respectively, for M. bicalcaratus in the presence of M. punctatus, but these differences were not significant. These results demonstrate asymmetric competition (at least as larvae) and indicate that M. punctatus is the superior competitor. Field data showed that M. bicalcaratus was found significantly more frequently in the absence of M. punctatus. Also, M. bicalcaratus populations were significantly more likely to go locally extinct in the presence of M. punctatus. These data suggest that asymmetric competitive interactions are important influences on the dynamics of these populations. [ABSTRACT FROM PUBLISHER]

In many organisms reproductive success is strongly dependent on several breeding site characteristics, which often vary in space and time. Although we have a good understanding of how ovipositing organisms respond to single factors, we still have little information about how they respond under more complex natural conditions. We examined the oviposition behavior of a tree-hole breeding frog,Phrynobatrachus guineensis, with respect to abiotic and biotic oviposition site characteristics, including desiccation risk and the presence of conspecific offspring using both observation and experiments. Based on daily monitoring data, compiled from 69 natural oviposition sites during a complete reproductive season, we developed oviposition site-selection models. A model based on water presence, sediment depth and maximal possible water depth showed the best predictive performance and was transferable to the subsequent season. Field observations and experiments revealed that frogs could estimate water-holding capacity of sites and timed oviposition with respect to future water presence. Despite the negative effects on larval growth and the availability of sites without conspecifics, data suggest that ovipositing individuals are attracted to conspecific offspring because they serve as a cue for low predation risk. Our results imply that a site’s potential for being used at least once for oviposition was determined by abiotic factors, whereas the relative use of breeding sites was determined by a response to conspecifics. Our study demonstrates the importance of including multiple biotic and abiotic factors in the analysis of oviposition site-selection. [ABSTRACT FROM AUTHOR]

Species diversity at the local-community scale can be altered by numerous factors, including disturbances, predators, and resource levels. Intermediate levels of these three factors are predicted, to enhance coexistence and diversity. However, no study has examined how these factors may interact to alter community, composition. The protozoan and rotifer community that colonized containers set in a forest was used to examine the interactions between these local community processes. We conducted a fully factorial microcosm experiment that manipulated disturbance frequency, predator density, and resource levels to examine protozoan and rotifer richness, community composition, and species abundance. Species richness was significantly altered by disturbances and predators, while predator densities interacted with disturbances and resources. Total abundance was significantly affected by each treatment, as well as a disturbance and predator interaction. We found that community composition was altered by each of the treatments and their interactions, indicating that different groups of species were present depending on the treatments. These results indicate that strong species sorting occurs in this community. Understanding these factors alone and in concert can provide insight to the potential complexities that underlie community structure and species composition. [ABSTRACT FROM AUTHOR]

Abstract. 1. Immatures of the invasive container mosquito Aedes albopictus occur in water-holding tanks and axils of ornamental bromeliads in Florida, where this species established and became abundant in the late 1980s and early 1990s. 2. The numbers of A. albopictus in bromeliads in gardens vary geographically in Florida, being significantly higher in northern sites where two species of Wyeomyia mosquitoes, native specialists of this microhabitat, are absent. 3. Causes of the negative relationship between abundances of A. albopictus and Wyeomyia spp. were investigated experimentally using Billbergia pyramidalis , an introduced bromeliad popular in Florida gardens. 4. Egg laying by A. albopictus in B. pyramidalis confined in a large outdoor cage was unaffected by the presence or absence of Wyeomyia spp. fourth instars, indicating that immatures of the native bromeliad mosquito species do not deter oviposition by the invasive species in this microhabitat. 5. Growth and survivorship of A. albopictus first instars in tanks of B. pyramidalis were negatively affected by the presence of fourth instar, but not first instar, Wyeomyia spp. larvae at natural densities. Stimulative effects of leaf litter on A. albopictus growth and survivorship in this microhabitat were independent of the presence or absence of Wyeomyia spp. immatures. 6. These results demonstrate that interspecific larval interactions regulate the production and explain the geographic patterns in abundance of A. albopictus from ornamental bromeliads in Florida. [ABSTRACT FROM AUTHOR]

Abstract A new genus and species, Nepenthacarus warreni , is described from adults, deutonymphs, protonymphs and larvae collected from the fluid-filled pitchers of Nepenthes mirabilis (Lour.) Druce in northern Queensland, Australia. [ABSTRACT FROM AUTHOR]

Phytotelmata habitats have been the focus of much research and are utilized by a wide variety of taxa. In the past 15 years numerous studies in many geographic regions and covering various types of phytotelmata have greatly increased our understanding of these unique habitats. The most recent summary of phytotelmata inhabitants included over 20 families of insects. A review of the literature and extensive work in lowland Ecuador shows the family level diversity is in fact at least twice that reported earlier. A reassessment of previous phytotelmata classification schemes, as well as an extensive bibliography, is provided. [ABSTRACT FROM PUBLISHER]