This dataset is associated with the published paper Escalante, I, M Domínguez, D Gómez-Ruiz, and G Machado. Benefits and costs of multi-specific aggregations in harvestmen (Arachnida: Opiliones). Frontiers in Ecology and Evolution (DOI 10.3389/fevo.2021.766323). Please refer to the paper for the extensive explanations on the collection, analysis, presentation, and analyses of the data. 

We provide the first description of mixed-species roosting aggregations of seven species of the genus Prionostemma from Costa Rica. We surveyed several plants (trees and palms) for the presence of harvestmen of seven different species across time (14 days). These harvestmen are frequently found in aggregations. Hence, we also counted the number of individuals in each aggregation. Additionally, we counted the number of legs in each harvestmen, as well as the number of parasitic mite larvae found in the harvestmen's bodies. With all of this information, we were able to explore the effects of the roosting status (solitary/aggregated), the aggregation size, and the species composition of the aggregations (single- or multi-species aggregations) with potential benefits (less damage, i.e., individuals with all of their legs) and costs (a higher parasitic infection).

We surveyed trees during the daytime looking for harvestmen roosting in solitary, in pairs, or in aggregations. We noted the number and species of all individuals in the group, and we noted the number of legs present, as well as the number of ectoparasitic mites.