The data presented here comes from samples collected as part of two recent research projects (ISLANDBIODIV and MACDIV), which aimed to understand the drivers of community assembly in Macaronesian islands. We applied the sampling protocol COBRA (Conservation Oriented Biodiversity Rapid Assessment, Cardoso 2009) in ten 50 m x 50 m native forest plots in the Azorean Islands of Pico (6 plots) and Terceira (10 plots) to assess the diversity of spiders species. Through this publication we contribute to the knowledge of the arachnofauna of the Azores, and more specifically, to that of the islands of Pico and Terceira. This dataset presents data generated from spider samples collected in 16 forest plots on the Azorean islands of Pico and Terceira. Of the 40 species collected, 16 were introduced, 13 endemic, seven native (five of them Macaronesian endemics) and four undescribed species. Although most of the species had been previously recorded on both islands, two of the introduced species were recorded in Pico for the first time.

The data we present are part of the long-term project SLAM (Long Term Ecological Study of the Impacts of Climate Change in the natural forest of Azores) that aims to understand the impact of biodiversity erosion drivers on Azorean native forests. Passive flight interception SLAM traps (Sea, Land and Air Malaise trap) were used to sample forest plots in both islands, with one trap being setup at each plot. A total of twenty 50m x 50m plots were sampled in two of the islands from the archipelago, 13 in Terceira and 7 in Pico. This publication contributes not only to a better knowledge of the arachnofauna present in native forests of Terceira and Pico, but also contributes to understand the patterns of abundance and diversity both seasonally and between years.

The data presented here comes from samples collected as part of one recent research project (MACDIV), which aimed to understand the drivers of community assembly in Macaronesian islands. We applied the sampling protocol COBRA (Conservation Oriented Biodiversity Rapid Assessment, Cardoso 2009) in twelve 50 m x 50 m native forest plots in the Madeira Island, five dry plots in Madeira Island and five dry plots in Porto Santo Island to assess the diversity of spiders species. Through this publication we contribute to the knowledge of the arachnofauna of the Madeira archipelago, and more specifically, to that of the islands of Madeira and Porto Santo. Of the 87 species and 18 morphospecies (undescribed) collected, 34 were endemic, 26 native non-endemic, 22 introduced and 23 species of unknown origin. Although most of the species had been previously recorded on both islands, 21 species are new records for Madeira island and 32 new for Porto Santo (33 for the whole archipelago).