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Specialists possess specialized trophic adaptations. Spiders of the genus Palpimanus Dufour, 1820 are araneophagous spiders which also catch alternative prey. They have morphological, behavioral, and venomic adaptations tuned to higher efficacy in the capture and processing of other spiders. Here, we tested the hypothesis whether Palpimanus can develop on two prey types. We reared spiderlings of Palpimanus spp. on a diet composed of spiders and of insects, and recorded their performance. We found that Palpimanus exhibited significantly higher mortality on the insect diet. In fact, only spiderlings on the spider diet were able to develop. The developmental rate was slow, as one instar lasted on average more than 60 days. On the basis of this finding, we estimated that the life cycle is at least biennial. We conclude that Palpimanus spiders possess specialized prey-capture adaptations towards spider prey which prevent them to utilize alternative prey. [ABSTRACT FROM AUTHOR]

Spiders are among the most taxonomically diversified orders of predators, but data on the trophic niche of most species are still unknown. Here, we investigated the fundamental trophic niche of two species of jumping spiders, Cyrba algerina (Lucas, 1846) and Heliophanus termitophagusWesołowska & Haddad, 2002, for which data on their realized trophic niche suggest trophic specialization (feeding on other spiders or termites, respectively). We investigated their fundamental trophic niche by means of acceptance experiments. Both species accepted a broader spectrum of prey under laboratory conditions than in the field, suggesting they are euryphagous specialists. [ABSTRACT FROM AUTHOR]

Online open databases are increasing in number, usefulness, and ease of use. There are currently two main global databases for spiders, the World Spider Catalogue (WSC) and the World Spider Trait (WST) database. Both are regularly used by thousands of researchers. Computational tools that allow effective processing of large data are now part of the workflow of any researcher and R is becoming a de facto standard for data manipulation, analysis, and presentation. Here we present an R package, arakno, that allows interface with the two databases. Implemented tools include checking species names against nomenclature of the WSC, obtaining and mapping data on distribution of species from both the WST and the Global Biodiversity Information Facility (GBIF), and downloading trait data from the WST. A set of tools are also provided to prepare data for further statistical analysis. [ABSTRACT FROM AUTHOR]

Spiders employ a wide range of foraging strategies and some are known to use conditional foraging behavior, which is tailored to the type of prey attacked. Little is known about the prey capture behavior of cribellate titanoecid spiders. Here, we investigated the fundamental trophic niche and predatory behavior of a cribellate-web spider, Titanoeca quadriguttata (Hahn, 1833). Juvenile spiders were collected under stones in a quarry and used in the experiment. We offered each individual nine prey types (spider, springtail, termite, cricket, cockroach, beetle, fly, moth, and ant) and observed the frequencies of capture and consumption, and the foraging behavior. We found that T. quadriguttata accepted many prey types, and thus, that its fundamental trophic niche was wide. The hunting behavior differed among prey types, depending on the size and potential danger of the prey. Two capture behaviors were used to overcome prey on the web. For dangerous and some large prey, such as spiders and crickets, the spider bit its victim and immediately retreated, whereas for innocuous and small prey, such as springtails and flies, the spider bit its victim and held it in the chelicerae. Attacks were administered to different body parts of prey. For example, ants were always bitten on the head, and crickets were bitten on the legs. We conclude that T. quadriguttata is an euryphagous generalist predator which uses conditional prey capture behavior to catch a variety of prey types. [ABSTRACT FROM AUTHOR]

In this study, field and laboratory observations of the feeding ecology (natural diet, prey acceptance, prey capture behavior and capture efficacy) of the theridiid Euryopis episinoides Walckenaer, 1847 were combined to reveal its trophic niche and capture efficacy and to test the hypothesis that this species is an ant-eating specialist. Natural prey was investigated from individuals collected in southern Portugal and was found to contain only ants of several species. Prey acceptance experiments revealed that spiders accepted several prey types occasionally, but ants, termites, and fruit flies were accepted with a high frequency. Prey capture behavior was similar for four tested prey types (Formicinae and Myrmicinae ants, termites, and fruit flies). Hunting usually started with a wrapping sequence when the spider threw the silk from its spinnerets onto the prey while circling around it. Then the spider bit the prey and wrapped it in more silk. Afterwards the spider waited for some time until the venom paralyzed the prey. Finally, the spider attached the immobilized prey to its spinnerets and carried it away before feeding. Wrapping time, number of bites, and waiting time differed among the four prey types, with the longest wrapping time, the highest number of bites, and the longest waiting time recorded during the capture of Myrmicinae ants. We conclude that E. episinoides is an ant-eating specialist possessing an effective capture strategy for the capture of ants. Yet, E. episinoides spiders maintain the ability to capture alternative prey. [ABSTRACT FROM AUTHOR]

Field and laboratory observations of the feeding ecology (natural diet, prey capture success, and prey handling) of Oecobius maculatus Simon 1870 were combined in this study to reveal the level of trophic specialization by this species. Natural prey were investigated on the Croatian island of Brac. Field observations revealed that although spiders captured prey belonging to five invertebrate orders, the most frequently captured prey were ants, which were also the most abundant available prey in the locality. In laboratory experiments, O. maculatus spiders accepted three other prey types with a higher probability than ants and were significantly more efficient at capturing and handling flies than ants. These results suggest that this species is a stenophagous generalist with a narrow prey range due to ecological circumstances. [ABSTRACT FROM AUTHOR]

A main goal of ecological and evolutionary biology is understanding and predicting interactions between populations and both abiotic and biotic environments, the spatial and temporal variation of these interactions, and the effects on population dynamics and performance. Trait-based approaches can help to model these interactions and generate a comprehensive understanding of ecosystem functioning. A central tool is the collation of databases that include species trait information. Such centralized databases have been set up for a number of organismal groups but is lacking for one of the most important groups of predators in terrestrial ecosystems - spiders. Here we promote the collation of an open spider traits database, integrated into the global Open Traits Network. We explore the current collation of spider data and cover the logistics of setting up a global database, including which traits to include, the source of data, how to input data, database governance, geographic cover, accessibility, quality control and how to make the database sustainable long-term. Finally, we explore the scope of research questions that could be investigated using a global spider traits database. [ABSTRACT FROM AUTHOR]