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Abstract Habitat choice is fundamental for an animal foraging, defense, and reproduction. Ogre-faced spiders are known for their unusual morphology, natural history, and rarity. They are sit-and-wait predators that build net-like webs that are manipulated by spiders and thrown at their prey. Hunting behavior includes selecting microhabitats for web construction that reduces the likelihood of damage or entanglement in the substrate during prey capture. Therefore, we expect that Deinopis cf. cylindracea selects smooth surfaces to forage on. We observed D. cf. cylindracea associated with smooth trunks of Plinia cauliflora (Myrtaceae) in the natural environment and actively selecting smooth trunks over rough trunks or litter in controlled experiments. Such selection is likely to maximize the foraging strategy of launching the web towards the substrate. Aggregations had occurred more often in the 50 cm trunk closest to the ground, where the prey community is largest. During the day, this spider appears to choose sites where it can adopt a stick-like posture upon the vegetation near the ground. Hunting at night and resting cryptically during the day appears to be shaped by natural selection for the survival and reproduction of this spider species. Resumo A escolha do habitat é fundamental para a busca de alimento, defesa e reprodução de um animal. As aranhas ogro são conhecidas por sua morfologia incomum, história natural e raridade. Elas são predadoras que ficam sentadas e esperam, construindo teias semelhantes a redes que são manipuladas por aranhas e lançadas em suas presas. O comportamento de caça inclui selecionar microhabitats para construção de teias que reduz a probabilidade de danos ou emaranhamento no substrato durante a captura da presa. Portanto, esperamos que Deinopis cf. cylindracea selecione superfícies lisas para forragear. Observamos D. cf. cylindracea associada a troncos lisos de Plinia cauliflora (Myrtaceae) no ambiente natural e selecionando ativamente troncos lisos em vez de troncos ásperos ou serapilheira em experimentos controlados. Essa seleção provavelmente maximiza a estratégia de forrageamento de lançar a teia em direção ao substrato. As agregações das aranhas ocorreram com mais frequência no tronco de 50 cm mais próximo do solo, onde a comunidade de presas é maior. Durante o dia, essa aranha parece escolher locais onde pode adotar uma postura semelhante a um graveto sobre a vegetação perto do chão. Caçar à noite e descansar enigmaticamente durante o dia parece ser moldado pela seleção natural para a sobrevivência e reprodução dessa espécie de aranha.

Abstract Frugivorous birds are important seed dispersers and influence the recruitment of many plant species in the rainforest. The efficiency of this dispersal generally depends on environment quality, bird species, richness and diversity of resources, and low levels of anthropogenic disturbance. In this study, we compared the sighting number of dusky-legged guans (Penelope obscura) by km and their movement in two areas of Serra do Japi, one around the administrative base (Base) where birds received anthropogenic food and a pristine area (DAE) with no anthropogenic resource. We also compared the richness of native seeds in feces of birds living in these two areas. Although the abundance of P. obscura was higher in the Base, these individuals moved less, dispersed 80% fewer species of plants and consumed 30% fewer seeds than individuals from DAE. The rarefaction indicated a low richness in the frugivorous diet of birds from the Base when compared to the populations from DAE. We conclude that human food supply can interfere in the behavior of these birds and in the richness of native seeds dispersed. Resumo Aves frugívoras são importantes dispersoras de sementes e influenciam no recrutamento de muitas espécies na floresta tropical. A eficiência dessa dispersão geralmente depende da qualidade do meio ambiente, das espécies de aves envolvidas, da riqueza e diversidade de recursos e de baixos níveis de impactos antrópicos. Neste estudo nós comparamos o número de avistamentos de jacuguaçus (Penelope obscura) por Km e seus movimentos em duas áreas na Serra do Japí, uma no entorno da base administrativa (Base) onde as aves receberam alimentos antropogênicos e outra em área pristina (DAE) sem fornecimento de alimentos humanos. Também comparamos a riqueza de sementes nativas nas fezes das aves que vivem nestas duas áreas. Embora a abundância de P. obscura tenha sido maior na Base, esses indivíduos deslocaram-se menos, dispersaram 80% menos espécies de plantas e consumiram 30% menos sementes do que os indivíduos do DAE. A rarefação indicou uma baixa riqueza na dieta frugívora das aves da Base quando comparada às populações do DAE. Concluímos que o fornecimento de alimentos humanos pode interferir no comportamento dessas aves e na riqueza de espécies de sementes nativas dispersadas.

Abstract Parental care has evolved numerous times in many taxonomic groups of animals. Matriphagy, as an extreme example of parental care, is present in many social species, subsocial species, and even in solitary spiders. Here, we describe matriphagy in five species of Anelosimus of different levels of sociality: social (A. dubiosus), intermediate social (A. jabaquara), subsocial (A. vierae, A. baeza), and solitary (A. nigrescens). Each group contained a female and its brood, maintained under standardized laboratory conditions. All species showed matriphagy, regardless of their social level. Further studies are necessary to clarify whether matriphagy is a necessary precondition for the evolution of sociality in spiders, or if it is phylogenetically conserved in some families.

Some parasitoids build a cocoon mass that hangs in the host body until the adults emergence, which is an advantage against attack by predators who troll the vegetation in search of prey. However, such behaviour is not effective against the hyperparasitoid attacks. This study reports the interaction between the caterpillar Manduca sexta Linnaeus, 1763 (Lepidoptera, Sphingidae) parasitised by Meteorus sp. (Hymenoptera, Braconidae) larvae and its hyperparasitoid Toxeumella albipes (Hymenoptera, Pteromalidae). This is the first description of the attack and oviposition of T. albipes. Alguns parasitoides constroem um agregado de casulos que fica pendurado no corpo do hospedeiro até a emergência dos adultos, o que é uma vantagem contra o ataque de predadores que vasculham a vegetação em busca de presas. No entanto, tal comportamento não é eficiente contra o ataque de hiperparasitoides. Este estudo registra a interação entre a lagarta Manduca sexta Linnaeus, 1763 (Lepidoptera, Sphingidae) parasitada por larvas de Meteorus sp. (Hymenoptera, Braconidae), e seu hiperparasitoide Toxeumella albipes (Hymenoptera, Pteromalidae). Esta é a primeira descrição do ataque e da oviposição de T. albipes.

Frugivorous birds are important seed dispersers and influence the recruitment of many plant species in the rainforest. The efficiency of this dispersal generally depends on environment quality, bird species, richness and diversity of resources, and low levels of anthropogenic disturbance. In this study, we compared the sighting number of dusky-legged guans (Penelope obscura) by km and their movement in two areas of Serra do Japi, one around the administrative base (Base) where birds received anthropogenic food and a pristine area (DAE) with no anthropogenic resource. We also compared the richness of native seeds in feces of birds living in these two areas. Although the abundance of P. obscura was higher in the Base, these individuals moved less, dispersed 80% fewer species of plants and consumed 30% fewer seeds than individuals from DAE. The rarefaction indicated a low richness in the frugivorous diet of birds from the Base when compared to the populations from DAE. We conclude that human food supply can interfere in the behavior of these birds and in the richness of native seeds dispersed.

Frugivorous birds are important seed dispersers and influence the recruitment of many plant species in the rainforest. The efficiency of this dispersal generally depends on environment quality, bird species, richness and diversity of resources, and low levels of anthropogenic disturbance. In this study, we compared the sighting number of dusky-legged guans (Penelope obscura) by km and their movement in two areas of Serra do Japi, one around the administrative base (Base) where birds received anthropogenic food and a pristine area (DAE) with no anthropogenic resource. We also compared the richness of native seeds in feces of birds living in these two areas. Although the abundance of P. obscura was higher in the Base, these individuals moved less, dispersed 80% fewer species of plants and consumed 30% fewer seeds than individuals from DAE. The rarefaction indicated a low richness in the frugivorous diet of birds from the Base when compared to the populations from DAE. We conclude that human food supply can interfere in the behavior of these birds and in the richness of native seeds dispersed.

Although specific associations between spiders and particular types of plants have been reported for several taxonomic groups, their consequences for spiders and plants are still poorly undertstood. The most common South American lynax spiders, Peucetia flava and P. rubrolineata, live strictly associated with various plant species that have glandular trichomes. To understand more about these spider—plant relationships, we investigated the influence of the spiders on the fitness of a neotropical glandular shrub (Trichogoniopsis adenantha) and on the arthroped community structure on the plant. We also tested whether glandular hairs provided any benefit to the spiders. Spiders reduced the abundance of several species and guilds of herbivores on the leaves and inflorescences. Consequently, damage to the leaves, capitula, ovaries, corollas, and stigmas caused by leaf-mining and chewing insects, as well as endophagous insects, were strongly reduced in the presence of Peucetia spp. Although the spiders fed on flower visitors, their negative influence on ovary fertilization was only marginally nonsignificant (P = 0.065). Spiders on plants of Trichogoniopsis adenantha that fed on common fruit files that had died before adhering to the glandular trichomes (Melissa officinalis) did not feed on dead on dead files and lost 13—20% of their biomass. These results indicate that Peucetia spiders are effective plant bodyguards and that when there is limited live prey they may feed on insect carcasses adhered to glandular trichomes. Since several spider species of the genus Peucetia live strictly associated with glandular trichome-bearing plants in neotropical, Neartic, Paleartic, and Afrotropical regions this type of facultative mutualism involving Peucetia and glandular plants mey be common worldwide.

Some parasitoids build a cocoon mass that hangs in the host body until the adults emergence, which is an advantage against attack by predators who troll the vegetation in search of prey. However, such behaviour is not effective against the hyperparasitoid attacks. This study reports the interaction between the caterpillar Manduca sexta Linnaeus, 1763 (Lepidoptera, Sphingidae) parasitised by Meteorus sp. (Hymenoptera, Braconidae) larvae and its hyperparasitoid Toxeumella albipes (Hymenoptera, Pteromalidae). This is the first description of the attack and oviposition of T. albipes.

1. In 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. 2. In 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. 3. Plants 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 fequently 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. 4. Our 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.

We examined the effects of the sit-and-wait spider Misumenops argenteus (Thomisidae) on the herbivore assemblage and fitness of the perennial woody shrub Trichogoniopsis adenantha (Asteraceae). Because crab spiders prey on both pollinators and phytophagous insects, they can have potentially negative and positive effects on plants. In a manipulative experiment using paired plants, spiders decreased the density of sucking and some endophagous herbivores on the leaves and capitula and reduced the number of damaged achenes produced by the plants. Damaged capitula had a higher proportion of fertilized achenes in plants with spiders than without spiders, but not undamaged capitula. These results indicate that M. argenteus exerted a double positive effect on seed production in T. adenantha. The effect of M. argenteus on herbivores may be taxon specific and vary among years with different herbivore abundances.