Ecological and evolutionary pathways of social behavior in Pseudoscorpions (Arachnida: Pseudoscorpiones)

Despite the great biodiversity in the Arachnida, some taxa are still now poorly known, mainly in terms of biology, ecology, and behavior. Pseudoscorpions are small arachnids (2–8 mm) that live in cryptic environments, being in general solitary predators of other invertebrates. The most studied Pseudoscorpion species are those from temperate areas, which revealed that Pseudoscorpiones present some level of sociality based on maternal care. Most developed sociality is seen in tropical species. Here, we reviewed this issue, presented examples of social behavior, and suggested the steps involved in the evolution of permanent sociality in the Neotropical Atemnidae genus, Paratemnoides. We discussed that the extended parental care, division of labor, cooperative breeding and feeding, and the tolerance among members dividing the same share could be considered enough to characterize a true social life, same in invertebrates.