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Jumping Spider (jumping + spider)
Selected AbstractsSpatial Distribution Patterns of Jumping Spiders Associated with Terrestrial BromeliadsBIOTROPICA, Issue 4 2004Gustavo Q. Romero ABSTRACT The jumping spiders Eustiromastix native, Psecas sumptuosus, and Uspachus sp. n. (Salticidae) live on terrestrial bro-meliads in areas with different phytophysiognomies in southeastern and northeastern Brazil. To understand these spider,plant interactions, we investigated if (1) these spiders were associated specifically with bromeliads, (2) the spiders utilized particular bromeliad species, and (3) plant size and density of bromeliads affected spider distribution. The jumping spiders were not found outside bromeliads, indicating a strict spider,plant association. Eustiromastix and Uspachus occupied bromeliads in open areas, whereas Psecas was found on forest bromeliads. Eustiromastix occurred at a higher frequency on larger bromeliads and in patches with higher bromeliad density. This is one of the few studies to demonstrate specific relationships between jumping spiders and a particular plant type. RESUMO As aranhas saltadoras Eustiromastix native, Psecas sumptuosus e Uspachus sp. n. (Salticidae) vivem sobre bromélias terrestres em áreas com diferentes fitofisionomias no sudeste e nordeste do Brasil. Para compreender estas interaçóes aranha-planta, nós investigamos se (1) estas aranhas estavam associadas especificamente a bromélias, (2) as aranhas utilizam espécies particulares de bromélias e (3) tamanho e densidade das bromélias afetam a distribuiçáo das aranhas. As aranhas saltadoras não foram encontradas fora das bromélias, indicando uma associaçáo estrita entre aranha e planta. Eustiromastix e Uspachus ocuparam bromelias em areas abertas enquanto Psecas foi encontrada em bromélias de floresta. Eustiromastix ocorreu em maior freqüéncia sobre bromélias maiores e em manchas com maior densidade de bromélias. Este estudo é um dos poucos a demonstrar relaço,es especificas entre aranhas saltadoras e um tipo particular de planta. [source] Jumping spiders (Araneae: Salticidae) that feed on nectarJOURNAL OF ZOOLOGY, Issue 1 2001Robert R. Jackson Abstract Nectivory was studied in 90 species from the spider family Salticidae. Observations of 31 of these species feeding on nectar from flowers in nature was the impetus for laboratory tests in which all 90 species fed from flowers. That sugar, not just water, is relevant to salticids was implied by choice tests where salticids spent more time drinking from a simulated nectar source (30% sucrose solution) than from distilled water. Our findings suggest that nectar feeding may be widespread, if not routine, in salticid spiders. [source] Signals and Signal Choices made by the Araneophagic Jumping Spider Portia fimbriata while Hunting the Orb-Weaving Web spiders Zygiella x-notata and Zosis geniculatusETHOLOGY, Issue 7 2000Michael Tarsitano Portia fimbriata is a web-invading araneophagic jumping spider (Salticidae). The use of signal-generating behaviours is characteristic of how P. fimbriata captures its prey, with three basic categories of signal-generating behaviours being prevalent when the prey spider is in an orb web. The predatory behaviour of P. fimbriata has been referred to as aggressive mimicry, but no previous studies have provided details concerning the characteristics of P. fimbriata's signals. We attempt to determine the model signals for P. fimbriata's ,aggressive mimicry' signals. Using laser Doppler vibrometer and the orb webs of Zygiella x-notata and Zosis geniculatus, P. fimbriata's signals are compared with signals from other sources. Each of P. fimbriata's three categories of behaviour makes a signal that resembles one of three signals from other sources: prey of the web spider (insects) ensnared in the capture zone of the web, prey making faint contact with the periphery of the web and large-scale disturbance of the web (jarring the spider's cage). Experimental evidence from testing P. fimbriata with two sizes of lure made from Zosis (dead, mounted in a lifelike posture in standard-size orb web) clarifies P. fimbriata's signal-use strategy: (1) when the resident spider is small, begin by simulating signals from an insect ensnared in the capture zone (attempt to lure in the resident spider); (2) when the resident spider is large, start by simulating signals from an insect brushing against the periphery of the web (keep the resident spider out in the web, but avoid provoking from it a full-scale predatory attack); (3) when walking in the resident spider's web, regardless of the resident spider's size, step toward the spider while making a signal that simulates a large-scale disturbance of the web (mask footsteps with a self-made vibratory smokescreen). [source] The effects of plant structure on the spatial and microspatial distribution of a bromeliad-living jumping spider (Salticidae)JOURNAL OF ANIMAL ECOLOGY, Issue 1 2005GUSTAVO Q. ROMERO Summary 1In several regions of South America, the neotropical jumping spider Psecas chapoda inhabits and reproduces strictly on the bromeliad Bromelia balansae. Previous studies reported that this spider is more frequent on bromeliads in grasslands than on those growing in forests, and on larger plants, but only when the bromeliads are without inflorescence. Upon blooming, B. balansae fold their leaves back, thereby changing the plant architecture from a tri-dimensional to a bi-dimensional flattened shape, and our hypothesis is that this alteration affects the spider's habitat-selection decisions. 2In the present study, we examined experimentally the effects of inflorescence, plant size and blockade of the axil of the leaves (spider shelters) of forest bromeliads on the colonization of a bromeliad by P. chapoda. By using sticky traps, we also compared prey availability in grassland and forest. 3Plants with simulated inflorescence were colonized at a lower frequency than those without inflorescence simulation. Grassland bromeliads in which the rosettes were blocked with dry leaves were colonized less frequently than open bromeliads, whereas forest bromeliads from which dry leaves had been removed were not colonized. Spiders generally abandoned bromeliads in which three-quarters of the length of the leaves had been removed, although females with eggsacs remained on these plants. Prey availability (biomass and number) was up to 18 fold higher in the grassland than in the forest. These results suggest that microhabitat structure and prey availability shape the spatial distribution of P. chapoda populations. 4Our findings suggest that Psecas chapoda can evaluate, in fine detail, the physical state of its microhabitat, and this unusual spider,plant association is readily destabilized by changes in the microhabitat (i.e., it is strictly dependent on the size and morphology of the host plant). This study is one of the few to report a strict association between a spider species and its host plant, and also one of the few to examine the effects of habitat and microhabitat structure on the spatial distribution of active hunters on plants. [source] Maternal care in a neotropical jumping spider (Salticidae)JOURNAL OF ZOOLOGY, Issue 3 2008C. Vieira Abstract Although female jumping spiders (Salticidae) often stay with their egg sacs, little is known about whether this behaviour is effective in improving offspring survival. Females of the jumping spider Psecas chapoda (Salticidae) typically stay above their egg sacs and under a plain silk cover, spun from edge to edge of bromeliad leaves. The objective of this paper is to test the hypothesis that the presence of the females above the egg sac increases egg survival. We experimentally manipulated females and silk cover in P. chapoda using three treatments: female and silk cover present (control), female removed and silk cover present and female and silk cover removed. The number and area of holes in the egg sac walls, which are likely to be damage caused by egg predators, were higher in the absence of spiders and spiders+silk cover than in controls. Additionally, the number of spiderlings and exuvia was lower in the absence of females and female+silk cover than in the control treatment. The number of important specialized predators of spider eggs (i.e. mantipids) that develop inside P. chapoda egg sacs did not differ among the treatments. To our knowledge, this is the first experimental study that effectively demonstrates maternal care in spiders of the family Salticidae. [source] Anti-predator crèches and aggregations of ant-mimicking jumping spiders (Araneae: Salticidae)BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 3 2008XIMENA J. NELSON Myrmarachne assimilis, an ant-like jumping spider (Araneae, Salticidae) from the Philippines and a Batesian mimic of Oecophylla smaragdina, the Asian weaver ant, aggregates on leaves in the company of its model. All stages in this species' lifecycle are sometimes found in nest complexes (nests connected to each other by silk). Although aggregating and forming nest complexes is known for a few other salticid species, the aggregations of M. assimilis have some unusual characteristics. In particular, reproductive females appear to be most frequently found with other reproductive females in nest complexes, suggesting that nest complexes have a role in parental care and are often built by females joining other females. An egg-survival experiment showed that eggs in solitary nests were more often destroyed than were eggs in nest complexes, suggesting that, for females of M. assimilis, choosing aggregations as oviposition sites may be functionally akin to life insurance for their progeny. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 94, 475,481. [source] Sexual dichromatism and male colour morph in ultraviolet-B reflectance in two populations of the jumping spider Phintella vittata (Araneae: Salticidae) from tropical ChinaBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2008JINGJING LI In the literature on animal use of ultraviolet (UV) vision and UV reflectance, it has usually been UV-A (315,400 nm) that is considered. Animals are generally assumed to be unable to discriminate UV-B (280,315 nm) from other wavelengths in natural sunlight. Recently, some animals are known to be able to detect and respond directly to UV-B in order to avoiding exposure to it. However, there is no evidence that the hue corresponding to UV-B is salient to an animal during intraspecies communication. Using Phintella vittata, an ornate jumping spider from two geographically different populations in China, we investigated geographical, intersexual, intrasexual, and interpopulation variation in UV reflectance. We found that both the males and the females of P. vittata reflect UV light, and that the reflection bands are located in UV-B, a part of reflectance spectrum never previously investigated. We also found a great deal of population variation in the UV-B spectral reflectance. Furthermore, two colour morphs, the ,green' and ,yellow' morphs, are identified for adult males for both populations, and both morphs differ greatly in both UV-B and human-visible wavelengths. This is the first demonstration of a UV-B reflecting salticid and UV-B sexual dichromatism. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 94, 7,20. [source] Maternal care in a neotropical jumping spider (Salticidae)JOURNAL OF ZOOLOGY, Issue 3 2008C. Vieira Abstract Although female jumping spiders (Salticidae) often stay with their egg sacs, little is known about whether this behaviour is effective in improving offspring survival. Females of the jumping spider Psecas chapoda (Salticidae) typically stay above their egg sacs and under a plain silk cover, spun from edge to edge of bromeliad leaves. The objective of this paper is to test the hypothesis that the presence of the females above the egg sac increases egg survival. We experimentally manipulated females and silk cover in P. chapoda using three treatments: female and silk cover present (control), female removed and silk cover present and female and silk cover removed. The number and area of holes in the egg sac walls, which are likely to be damage caused by egg predators, were higher in the absence of spiders and spiders+silk cover than in controls. Additionally, the number of spiderlings and exuvia was lower in the absence of females and female+silk cover than in the control treatment. The number of important specialized predators of spider eggs (i.e. mantipids) that develop inside P. chapoda egg sacs did not differ among the treatments. To our knowledge, this is the first experimental study that effectively demonstrates maternal care in spiders of the family Salticidae. [source] Anti-predator crèches and aggregations of ant-mimicking jumping spiders (Araneae: Salticidae)BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 3 2008XIMENA J. NELSON Myrmarachne assimilis, an ant-like jumping spider (Araneae, Salticidae) from the Philippines and a Batesian mimic of Oecophylla smaragdina, the Asian weaver ant, aggregates on leaves in the company of its model. All stages in this species' lifecycle are sometimes found in nest complexes (nests connected to each other by silk). Although aggregating and forming nest complexes is known for a few other salticid species, the aggregations of M. assimilis have some unusual characteristics. In particular, reproductive females appear to be most frequently found with other reproductive females in nest complexes, suggesting that nest complexes have a role in parental care and are often built by females joining other females. An egg-survival experiment showed that eggs in solitary nests were more often destroyed than were eggs in nest complexes, suggesting that, for females of M. assimilis, choosing aggregations as oviposition sites may be functionally akin to life insurance for their progeny. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 94, 475,481. [source] Innate aversion to ants (Hymenoptera: Formicidae) and ant mimics: experimental findings from mantises (Mantodea)BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2006XIMENA J. NELSON Field data suggest that ants may be important predators of mantises which, in turn, may be important predators of jumping spiders (Salticidae). Using a tropical fauna from the Philippines as a case study, the reactions of mantises to ants, myrmecomorphic salticids (i.e. jumping spiders that resemble ants) and ordinary salticids (i.e. jumping spiders that do not resemble ants) were investigated in the laboratory. Three mantis species (Loxomantis sp., Orthodera sp., and Statilia sp.) were tested with ten ant species, five species of Myrmarachne (i.e. myrmecomorphic salticids), and 23 ordinary salticid species. Two categories of the myrmecomorphic salticids were recognized: (1) ,typical Myrmarachne' (four species with a strong resemblance to ants) and (2) Myrmarachne bakeri (a species with less strong resemblance to ants). Ants readily killed mantises in the laboratory, confirming that, for the mantises studied, ants are dangerous. In alternate-day testing, the mantises routinely preyed on the ordinary salticids, but avoided ants. The mantises reacted to myrmecomorphic salticids similarly to how they reacted to ants (i.e. myrmecomorphic salticids appear to be, for mantises, Batesian mimics of ants). Although myrmecomorphic salticids were rarely eaten, M. bakeri was eaten more often than typical Myrmarachne. Because the mantises had no prior experience with ants, ant mimics or ordinary salticids, our findings suggest that mantises have an innate aversion to attacking ants and that this aversion is generalized to myrmecomorphic salticids even in the absence of prior experience with ants. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society, 2006, 88, 23,32. [source] Spatial Distribution Patterns of Jumping Spiders Associated with Terrestrial BromeliadsBIOTROPICA, Issue 4 2004Gustavo Q. Romero ABSTRACT The jumping spiders Eustiromastix native, Psecas sumptuosus, and Uspachus sp. n. (Salticidae) live on terrestrial bro-meliads in areas with different phytophysiognomies in southeastern and northeastern Brazil. To understand these spider,plant interactions, we investigated if (1) these spiders were associated specifically with bromeliads, (2) the spiders utilized particular bromeliad species, and (3) plant size and density of bromeliads affected spider distribution. The jumping spiders were not found outside bromeliads, indicating a strict spider,plant association. Eustiromastix and Uspachus occupied bromeliads in open areas, whereas Psecas was found on forest bromeliads. Eustiromastix occurred at a higher frequency on larger bromeliads and in patches with higher bromeliad density. This is one of the few studies to demonstrate specific relationships between jumping spiders and a particular plant type. RESUMO As aranhas saltadoras Eustiromastix native, Psecas sumptuosus e Uspachus sp. n. (Salticidae) vivem sobre bromélias terrestres em áreas com diferentes fitofisionomias no sudeste e nordeste do Brasil. Para compreender estas interaçóes aranha-planta, nós investigamos se (1) estas aranhas estavam associadas especificamente a bromélias, (2) as aranhas utilizam espécies particulares de bromélias e (3) tamanho e densidade das bromélias afetam a distribuiçáo das aranhas. As aranhas saltadoras não foram encontradas fora das bromélias, indicando uma associaçáo estrita entre aranha e planta. Eustiromastix e Uspachus ocuparam bromelias em areas abertas enquanto Psecas foi encontrada em bromélias de floresta. Eustiromastix ocorreu em maior freqüéncia sobre bromélias maiores e em manchas com maior densidade de bromélias. Este estudo é um dos poucos a demonstrar relaço,es especificas entre aranhas saltadoras e um tipo particular de planta. [source] | ||||||||||