Intraspecific variation in responses to aposematic prey in a jumping spider (Phidippus regius)

Aposematic signals often allow chemically defended prey to avoid attack from generalist predators, including jumping spiders. However, not all individual predators in a population behave in the same way. Here, in laboratory trials, we document that most individual Phidippus regius jumping spiders attack and reject chemically defended milkweed bugs (Oncopeltus fasciatus), immediately releasing them unharmed. However, a small number of individuals within the population kill and completely consume these presumably toxic prey items. This phenomenon was infrequent with only 14% of our sample (17/122) consuming the milkweed bugs over the course of the study. Individuals that killed and consumed bugs often did so repeatedly; specifically, individuals that consumed a bug in their first test were more likely to kill a bug in their second test and also tended to consume them again. We explored what might drive some (but not all) individuals to consume these bugs and found that neither sex, sexual maturity, body size, laboratory housing type, nor being wild-caught or being laboratory-reared, predicted milkweed bug consumption. Consuming bugs had no negative effects on spider mass or body condition; contrary to expectations, individuals that consumed milkweed bugs actually gained more body mass and increased in body condition. We discuss potential behavioural and physiological variation between individuals that may drive these rare behaviours and the implications for the evolution of prey defences.     

Control of aphids on wheat by generalist predators: effects of predator density and the presence of alternative prey

There is evidence for both positive and negative effects of generalist predators on pest populations and the various reasons for these contrasting observations are under debate. We studied the influence of a generalist predator, Pardosa lugubris (Walckenaer) (Araneae: Lycosidae), on an aphid pest species, Rhopalosiphum padi (L.) (Hemiptera: Aphididae; low food quality for the spider), and its host plant wheat, Triticum spec. (Poaceae). We focused on the role of spider density and the availability of alternative prey, Drosophila melanogaster Meigen (Diptera: Drosophilidae; high food quality). The presence of spiders significantly affected plant performance and aphid biomass. Alternative prey and spider density strongly interacted in affecting aphids and plants. High spider density significantly improved plant performance but also at low spider density plants benefited from spiders especially in the presence of alternative prey. The results suggest that generalist arthropod predators may successfully reduce plant damage by herbivores. However, their ability to control prey populations varies with predator nutrition, the control of low-quality prey being enhanced if alternative higher-quality prey is available.     

Management strategy, shade, and landscape composition effects on urban landscape plant quality and arthropod abundance

Intensity and type of management, the cultural variable shade, and the combination of woody and herbaceous annual and perennial plants were evaluated for their effect on key landscape arthropod pests. Azalea lace bugs, Stephanitis pyrioides (Scott), and twolined spittlebugs, Prosapia bicincta (Say), were most effectively suppressed in landscape designed with resistant plant species of woody ornamentals and turf. Landscapes containing susceptible plant counterparts were heavily infested by these two insect species in untreated control plots. A traditional management program of prescribed herbicide, insecticide, and fungicide applications effectively suppressed azalea lace bug and produced a high-quality landscape. Targeted integrated pest management with solely horticultural oils resulted in intermediate levels of azalea lace bug. Neither program completely controlled twolined spittlebug on hollies or turf. Carabidae, Staphylinidae, Formicidae, and Araneae were not reduced by any management strategy. Lace bugs (Stephanitis) were more common in plots with 50% shade than those in full sun. Spittlebugs (Prosapia) were more common in the shade during 1996 and in the sun during 1997. Spiders and ants were more often collected in full sun plots. Carabids, staphylinids, and spiders were more commonly collected from pitfall traps in turf than in wood-chip mulched plant beds, whereas ants were equally common in both locations. The addition of herbaceous plants to the landscape beds had little effect on pest insect abundance.     

Shade Tree Diversity,Cocoa Pest Damage,Yield Compensating Inputs and Farmers' Net Returns in West Africa

Cocoa agroforests can significantly support biodiversity, yet intensification of farming practices is degrading agroforestry habitats and compromising ecosystem services such as biological pest control. Effective conservation strategies depend on the type of relationship between agricultural matrix, biodiversity and ecosystem services, but to date the shape of this relationship is unknown. We linked shade index calculated from eight vegetation variables, with insect pests and beneficial insects (ants, wasps and spiders) in 20 cocoa agroforests differing in woody and herbaceous vegetation diversity. We measured herbivory and predatory rates, and quantified resulting increases in cocoa yield and net returns. We found that number of spider webs and wasp nests significantly decreased with increasing density of exotic shade tree species. Greater species richness of native shade tree species was associated with a higher number of wasp nests and spider webs while species richness of understory plants did not have a strong impact on these beneficial species. Species richness of ants, wasp nests and spider webs peaked at higher levels of plant species richness. The number of herbivore species (mirid bugs and cocoa pod borers) and the rate of herbivory on cocoa pods decreased with increasing shade index. Shade index was negatively related to yield, with yield significantly higher at shade and herb covers<50%. However, higher inputs in the cocoa farms do not necessarily result in a higher net return. In conclusion, our study shows the importance of a diverse shade canopy in reducing damage caused by cocoa pests. It also highlights the importance of conservation initiatives in tropical agroforestry landscapes.     

Attraction of a generalist predator towards herbivore-infested plants

The occurrence and strength of interactions among natural enemies and herbivores depend on their foraging decisions, and several of these decisions are based on odours. To investigate interactions among arthropods in a greenhouse cropping system, we studied the behavioural response of the predatory bug Orius laevigatus (Fieber) (Hemiptera: Anthocoridae) towards cucumber plants infested either with thrips (Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae)) or with spider mites (Tetranychus urticae Koch (Acari: Tetranychidae)). In greenhouse release-recapture experiments, the predatory bug showed a significant preference for both thrips-infested plants and spider mite-infested plants over clean plants. Predatory bugs preferred plants infested with spider mites to plants with thrips. Experience with spider mites on cucumber leaves prior to their release in the greenhouse had no effect on the preference of the predatory bugs. However, this experience did increase the percentage of predators recaptured. Y-tube olfactometer experiments showed that O. laevigatus was more attracted to odours from plants infested with spider mites than to odours from clean plants. Thus, O. laevigatus is able to perceive odours and may use them to find plants with prey in more natural conditions. The consequences of the searching behaviour for pest control are discussed.     

Experimental assessment of trophic ecology in a generalist spider predator: Implications for biocontrol in Uruguayan crops

Conservative biological control promotes the use of native natural enemies to limit the size and growth of pest populations. Although spiders constitute one of the most important groups of native predators in several crops, their trophic ecology remains largely unknown, especially for several generalist taxa. In laboratory, we assessed the predatory behaviour of a wandering spider (the wolf spider Lycosa thorelli (Keyserling, 1877) against several arthropods varying in size and trophic positions, all found in South American soybean and rice crops. As prey we used the bug Piezodorus guildinii (Westwood, 1837) as well as larvae and adults of the moth Spodoptera frugiperda (Smith, 1797), both being considered important pests in Uruguayan crops. We also used several non-pest arthropods as prey, sarcophagid flies, carabid beetles and wolf spiders. All prey were attacked in more or less high, although not statistically differing, proportions. However, carabids were not consumed, and bugs were consumed in significantly lower proportions than flies. A negative correlation was found between prey size and acceptance rate. Immobilization times were longer against larvae when compared to moths and flies, while predatory sequences were longer for bugs when compared to flies, moths and spiders. In addition, we found a positive effect of prey size on predatory sequence length and complexity. Our results confirm the ability of spiders to attack and feed upon prey with different morphologies, included well-defended arthropods, and their potential use as natural enemies of several pests in South American crops.     

Niches and interspecific competitions of wolf spiders and mirid bug, Cyrtorhinus lividipennis under three pest management strategies in paddy fields

The duck-rice and fish-rice were two important strategies of pest management in the process of organic rice. The niches and interspecific competitions of wolf spiders and mirid bug, Cyrtorhinus lividipennis under three strategies of pest management in paddy fields were studied in order to understand the influences of different pest control methods on ecological relationships between the two main types of predators. The results of our study suggested that ducks might prey upon wolf spiders resting on the base of rice plants, thus the populations of wolf spiders decreased in duck-rice treatment. The impact of ducks on mirid bug was not significant because it preferred to congregate on the mid-part of rice plants. The temporal selectivity of wolf spiders was smaller than that of mirid bug, which meant occurrence frequency of wolf spiders was higher compared with mirid bug. In addition, competition between wolf spiders and mirid bug was significantly more intense in duck-rice or fish-rice treatment than in natural control treatment at different stages. Probably, ducks and fishes drove wolf spiders away from their original spatial niche, the base to the mid-part in rice plants, enhancing competition between wolf spiders and mirid bug in duck-rice or fish-rice treatment. Based on the results of this study, duck-rice or fish-rice, as a control pest method in the process of organic rice, should be prudentially treated.     

Niches and interspecific competitions of wolf spiders and mirid bug, Cyrtorhinus lividipennis under three pest management strategies in paddy fields

The duck-rice and fish-rice were two important strategies of pest management in the process of organic rice. The niches and interspecific competitions of wolf spiders and mirid bug, Cyrtorhinus lividipennis under three strategies of pest management in paddy fields were studied in order to understand the influences of different pest control methods on ecological relationships between the two main types of predators. The results of our study suggested that ducks might prey upon wolf spiders resting on the base of rice plants, thus the populations of wolf spiders decreased in duck-rice treatment. The impact of ducks on mirid bug was not significant because it preferred to congregate on the mid-part of rice plants. The temporal selectivity of wolf spiders was smaller than that of mirid bug, which meant occurrence frequency of wolf spiders was higher compared with mirid bug. In addition, competition between wolf spiders and mirid bug was significantly more intense in duck-rice or fish-rice treatment than in natural control treatment at different stages. Probably, ducks and fishes drove wolf spiders away from their original spatial niche, the base to the mid-part in rice plants, enhancing competition between wolf spiders and mirid bug in duck-rice or fish-rice treatment. Based on the results of this study, duck-rice or fish-rice, as a control pest method in the process of organic rice, should be prudentially treated.     

Prey preference,intraguild predation and population dynamics of an arthropod food web on plants

The theory of intraguild predation (IGP) largely studies effects on equilibrium densities of predators and prey, while experiments mostly concern transient dynamics. We studied the effects of an intraguild (IG) predator, the bug Orius laevigatus, on the population dynamics of IG-prey, the predatory mite Phytoseiulus persimilis, and a shared prey, the phytophagous two-spotted spider mite Tetranychus urticae, as well as on the performance of cucumber plants in a greenhouse. The interaction of the predatory mite and the spider mite is highly unstable, and ends either by herbivores overexploiting the plant or predators exterminating the herbivores. We studied the effect of IGP on the transient dynamics of this system, and compared the dynamics with that predicted by a simple population-dynamical model with IGP added. Behavioural studies showed that the predatory bug and the predatory mite were both attracted to plants infested by spider mites and that the two predators did not avoid plants occupied by the other predator. Observations on foraging behaviour of the predatory bug showed that it attacks and kills large numbers of predatory mites and spider mites. The model predicts strong effects of predation and prey preference by the predatory bugs on the dynamics of predatory mites and spider mites. However, experiments in which the predatory bug was added to populations of predatory mites and spider mites had little or no effect on numbers of both mite species, and cucumber plant and fruit weight.     

Effects of tree species diversity on a community of weaver spiders in a tropical forest plantation

The effects of producer diversity on predators have received little attention in arboreal plant communities, particularly in the tropics. This is particularly true in the case of tree diversity effects on web‐building spiders, one of the most important groups of invertebrate predators in terrestrial plant communities. We evaluated the effects of tree species diversity on the community of weaver spiders associated with big‐leaf mahogany (Swietenia macrophylla) in 19, 21 × 21‐m plots (64 plants/plot) of a tropical forest plantation which were either mahogany monocultures (12 plots) or polycultures (seven plots) that included mahogany and three other tree species. We conducted two surveys of weaver spiders on mahogany trees to evaluate the effects of tree diversity on spider abundance, species richness, diversity, and species composition associated with mahogany. Our results indicated that tree species mixtures exhibited significantly greater spider abundance, species richness, and diversity, as well as differences in spider species composition relative to monocultures. These results could be due to species polycultures providing a broader range of microhabitat conditions favoring spider species with different habitat requirements, a greater availability of web‐building sites, or due to increased diversity or abundance of prey. Accordingly, these results emphasize the importance of mixed forest plantations for boosting predator abundance and diversity and potentially enhancing herbivore pest suppression. Future work is necessary to determine the specific mechanisms underlying these patterns as well as the top‐down effects of increased spider abundance and species richness on herbivore abundance and damage.     

Spider predation on a mirid pest in Japanese rice fields

Spiders are common generalist predators, and understanding their potential in biological control is important for the development of integrated pest management programs. In this study, predation by three groups of spiders on the mirid bug Stenotus rubrovittatus (Hemiptera: Miridae) in rice paddies was investigated using DNA-based gut-content analysis. A laboratory feeding study revealed that the detection half-lives of bug DNA in the spider gut at 25 °C was 3.4 days for Lycosidae and 1.5 days for Tetragnathidae. Individual spider predation on the mirid bug was investigated by detecting DNA of prey in field-collected spiders. In total, 1199 spiders were assayed from three spider groups: Pirata subpiraticus (Lycosidae), Tetragnatha spp. (Tetra-gnathidae), and Pachygnatha clercki (Tetra-gnathidae), which each differ in their preferred microhabitat as well as their predatory habits. Detection rates of prey DNA in spiders increased significantly with the density of prey across all spider groups. P. subpiraticus and Tetragnatha spp. predation showed a better fit to a saturated response curve to increasing prey density, while P. clercki showed a simple linear relationship with prey density. Densities of alternative prey species did not affect the detection rates of mirids. These results suggest that predation on pests by generalist predators in an agroecosystem is affected not only by prey abundance but also by predator preference for specific prey. Predator preference is therefore an important factor to consider when estimating the role of natural enemies as biological control agents.     

Impact of flower-dwelling crab spiders on plant-pollinator mutualisms

Indirect effects in interactions occur when a species influences a third species by modifying the behaviour of a second one. It has been suggested that indirect effects of crab spiders (Thomisidae) on pollinator behaviour can cascade down the food web and negatively affect plant fitness. However, it is poorly understood how different pollinator groups react to crab spiders and, thus, when a reduction in plant fitness is likely to occur. Using continuous video surveillance, we recorded the behaviour of pollinators on two flower species and the pollinators’ responses to three crab spider treatments: inflorescences (1) with a pinned dried spider, (2) with a spider model made of paper, and (3) without spiders (control). We found that pollinators avoided inflorescences with dried spiders only on one plant species (Anthemis tinctoria). Pollinators showed no significant avoidance of paper spiders. Honeybees and bumblebees did not react to dried spiders, but solitary bees and syrphid flies showed a strong avoidance. Finally, we found no evidence that inflorescences with dried spiders suffered from a decrease in fitness in terms of a reduced seed set. We hypothesise that top-down effects of predators on plants via pollinators depend on the degree of specialisation of pollinators and their tendency to avoid spiders.     

Spider silk reduces insect herbivory

The role of predators in food webs extends beyond their ability to kill and consume prey. Such trait-mediated effects occur when signals of the predator influence the behaviour of other animals. Because all spiders are silk-producing carnivores, we hypothesized that silk alone would signal other arthropods and enhance non-lethal effects of spiders. We quantified the herbivory inflicted by two beetle species on green bean plants (Phaseolus vulgaris) in the presence of silkworm silk and spider silk along with no silk controls. Single leaflets were treated and enclosed with herbivores in the laboratory and field. Another set of leaflets were treated and left to experience natural herbivory in the field. Entire plants in the field were treated with silk and enclosed with herbivores or left exposed to herbivory. In all cases, the lowest levels of herbivory occurred with spider silk treatments and, in general, silkworm silk produced intermediate levels of leaf damage. These results suggest that silk may be a mechanism for the trait-mediated impacts of spiders and that it might contribute to integrated pest management programmes.     

Predatory behaviour of an araneophagic assassin bug

Assassin bugs from the genus Stenolemus (Heteroptera, Reduviidae) are predators of web-building spiders. However, despite their fascinating lifestyle, little is known about how these insects hunt and catch their dangerous prey. Here we characterise in detail the behaviour adopted by Stenolemus bituberus (Stål) during encounters with web-building spiders, this being an important step toward understanding this species’ predatory strategy. These bugs employed two distinct predatory tactics, “stalking” and “luring”. When stalking their prey, bugs slowly approached the prey spider until within striking range, severing and stretching threads of silk that were in the way. When luring their prey, bugs attracted the resident spider by plucking and stretching the silk with their legs, generating vibrations in the web. Spiders approached the luring bug and were attacked when within range. The luring tactic of S. bituberus appears to exploit the tendency of spiders to approach the source of vibrations in the web, such as might be generated by struggling prey.     

The lethal and sublethal effects of three pesticides on the striped lynx spider (Oxyopes salticus Hentz)

The striped lynx spider, Oxyopes salticus Hentz, is found in high abundances in agricultural fields where it forages on many agricultural pests. Pesticides are applied to these fields and can therefore impact these natural pest predators. Researchers have examined the effects of a number of pesticides on this spider and other pest predators, but many of these studies only examine how these pesticides affect mortality. More recently, researchers have begun to examine the sublethal effects of these chemicals. We examined both the lethal and sublethal effects of three common pesticides with the active ingredients bifenthrin, carbaryl and malathion. We found that only malathion significantly reduced the post‐exposure lifespan of these spiders; however, each pesticide had sublethal effects on behaviour. Exposure to malathion reduced jumping, likely an important foraging and escape behaviour. Spiders exposed to bifenthrin spent increased time grooming, which can reduce the time spent performing other important behaviours. Finally, spiders that were exposed to carbaryl surprisingly increased their prey capture rate. We show here that pesticides can not only directly affect the lifespan of the striped lynx spider but that each pesticide can cause different sublethal effects that likely impact the survival and ecology of these important pest predators.     

How leaf domatia and induced plant resistance affect herbivores, natural enemies and plant performance

Predators and plant resistance may act together to control herbivorous arthropod populations or antagonistically, which would reduce the control of pest populations. In a field experiment we enhanced predation by adding simulated leaf domatia to plants. Leaf domatia are small structures that often harbor predaceous arthropods that are potentially beneficial to the plant. We also manipulated host plant quality by inducing resistance with controlled, early season exposure of seedlings to spider mite herbivory.
Our manipulations had profound consequences for the natural community of arthropods that inhabited the plants. Leaf domatia had a direct positive effect on abundances of two species of bugs and one species of thrips, all of which are largely predators of herbivores. On leaves with domatia, each of the predators was found inside the domatia two to three times more often than outside the domatia. Eggs of predaceous bugs inside leaf domatia were protected from parasitism compared to eggs outside the domatia. The positive effects of leaf domatia on predator abundances were associated with reduced populations of herbivorous spider mites, aphids, and whiteflies. Plants with experimental leaf domatia showed significantly enhanced reproductive performance.
Induced resistance also affected the community of arthropods. Of the abundant predators, all of which also fed on the plant, only minute pirate bugs were negatively affected by induced resistance. Populations of herbivorous spider mites and whiteflies were directly and negatively affected by induction. In contrast, aphid populations were higher on plants with induced resistance compared to uninduced plants. Effects of induced resistance and domatia were additive for each of the predators and for aphids. However, spider mite and whitefly populations were not suppressed further by employing both induced resistance and domatia compared to each strategy alone. Our manipulations suggest that plant defense strategies can have positive effects on some species and negative effects on others. Negative effects of “resistance traits” on predators and positive effects on some herbivores may reduce the benefits of constitutive expression of resistance traits and may favor inducible defense strategies. Multiple plant strategies such as inducible resistance and morphological traits that aid in the recruitment of predators of herbivores may act together to maximize plant defenses, although they may also be redundant and not act additively.     

Consumptive and non‐consumptive effects of wolf spiders on cucumber beetles and cucumber plant damage

Biological control research often focuses on the ability of predators to reduce pest densities and protect crops through consumption. Less studied is their ability to protect crops by altering pest behaviour (non‐consumptive effects). Lab experiments were conducted to test predation rates of striped cucumber beetles (Acalymma vittatum; Coleoptera: Chrysomelidae) and spotted cucumber beetles (Diabrotica undecimpunctata howardi; Coleoptera: Chrysomelidae) by large (>10 mm) wolf spiders (Araneae: Lycosidae). Field experiments were conducted to examine how the physical presence and/or cues of spiders impact the behaviour and mortality of A. vittatum (specialist) and D. undecimpunctata (generalist) cucumber beetles as well as growth and damage of cucumber plants (Cucumis sativus; Cucurbitaceae). A. vittatum and D. undecimpunctata adults were added to caged cucumber plants without a spider, with spider cues only (spider removed before beetle inclusion), with spider only (spider introduced to plants immediately before beetle inclusion), and with spiders and their cues present (spiders introduced 24 hr in advance of beetle inclusion). A. vittatum responded to spider cues primarily by emigrating from plants. Contrarily, D. undecimpunctata did not display obvious responses, such as reduced feeding or increased emigration, to spider foraging and/or cues. Actively foraging lycosids increased A. vittatum mortality and reduced densities of D. undecimpunctata in the field when cucumber plants were flowering. This study highlights how non‐consumptive and consumptive effects can play a role in modifying pest populations, and how these effects can vary across species and plant growth stages.     

臭虫的再猖獗、生物学及防治研究进展

由于DDT等现代杀虫剂的问世,臭虫在20世纪40-50年代以后在全球大部分地区尤其是发达国家和地区销声匿迹,但近10多年来臭虫在部分国家和地区重新出现.本文对其再猖獗原因、生物学和行为、饲养、抗药性、监测与防治策略进行了综述,旨在引起国人的重视,对今后臭虫的监测和防治起到抛砖引玉的作用.本文分析了近15年有关温带臭虫Cimex lectulariusL.和热带臭虫C.hemipterus(F.)的研究文献.臭虫再猖獗被认为是因为它对目前使用的杀虫剂例如拟除虫菊酯类等产生抗性以及频繁的地区及国际交往等因素造成的.简单、经济和大规模臭虫种群饲养方法——人工膜饲喂法的研发为我们开展臭虫生物学和生态学研究提供了便利.控制和根除臭虫目前仍较困难,采用害虫综合治理(integrated pest management,IPM)策略,包括臭虫知识宣传、主动监测、非化学防治方法(例如:经常洗涤床上用品、蒸汽熏蒸、热处理、使用床垫罩、在家具腿下放置臭虫拦截装置)、有选择使用杀虫剂以及定期监测及反复防治等措施,可达到很好的防控效果.在我国部分地区,臭虫发生也呈上升趋势,工人宿舍和火车车厢是常见的臭虫为害环境.有必要对我国臭虫发生现状及其抗药性进行调查与监测.还应借鉴国际先进技术,研制出我国适用的、有效的监测工具和防治方法,并根据我国具体国情制定出切实可行的防治标准.同时积极开展臭虫科普宣传,做到早发现、早防治,防止臭虫再猖獗和扩散.     

Bromeliads provide shelter against fire to mutualistic spiders in a fire‐prone landscape

1. A key challenge in the study of mutualistic interactions is understanding sources of variation that strengthen or weaken these interactions. In spider–plant mutualisms, spiders benefit plants by improving plant nutrition and protecting plants from herbivory. Although the benefits of plants to spider growth and survival are often claimed, they are rarely demonstrated. 2. In this study, empirical evidence is provided that bromeliads (Bromelia balansae, Bromeliaceae) are essential for the resilience of the mutualistic bromeliad‐living jumping spider populations (Psecas chapoda, Salticidae) after a fire event, sheltering spiders from the heat of the flames. 3. Spider populations were compared before and after a natural fire event and it was shown that spiders of different ages survived the fire. The survival of such individuals allowed the population of P. chapoda spiders to recover rapidly, returning to pre‐fire levels in 5 months. 4. Bromeliads reduced the susceptibility of P. chapoda spiders to burning, and this mutualistic relationship contributed to the resilience of the spider population after a fire event. It is suggested that frequent fires in fire‐prone landscapes may have strengthened this spider–plant relationship, contributing to the maintenance and evolution of this association.     

Induced indirect defence in a spider–plant system mediated by pericarpial nectaries

Some plant species attacked by herbivore species produce additional resources to attract predators and induce an indirect defence process. We evaluated whether Palicourea rigida (Rubiaceae) individuals can induce indirect defences as response to herbivory simulation by increasing pericarpial nectar production and volatile emissions, as well as whether spiders are attracted by such induced indirect defences. We selected 30 P. rigida individuals and simulated herbivory in 15 of them by cutting out half of all leaves using pruning shears. We did not manipulate the other 15 plants (control group). At three different times, we measured nectar volume and calories of the pericarpial nectary in the inflorescences of all plants of control and treatment groups. We also quantified spider abundance on these plants. In another experiment, we selected salticid spider, Thiodina sp., to determine whether predators detect chemical tracks of plant volatiles produced by the plant after herbivory simulations. We also tested whether the honey solution could emit olfactory signals capable of attractive spiders. We showed that P. rigida produced higher volume of pericarpial nectar presenting more calories after herbivory simulation. The abundance of spiders was higher in plants subjected to herbivory simulation than control plants. Thiodina sp. did not respond to the volatile chemical tracks produced by the leaves after the simulation, but it had a positive response to olfactory tracks associated with the sucrose solution. Such an outcome indicates the ability of this spider to locate nectar honey plants and olfactory signals of honey. Thus, plants respond to the action of herbivores by producing more pericarpial nectar and nectar with more calories. Although our knowledge about the olfactory physiology of arachnids remains incipient, we highlight the importance of chemical and olfactory tracks for decision‐making of spiders in foraging on plants and the herbivory influence on the behaviour of cursorial spiders.