História natural e comportamento no pseudoescorpião social Paratemnoides nidificator (Balzan, 1888) (Arachnida) : cuidado parental, cooperação e divisão de trabalho

Abstract

The social behavior is rare among the arachnids. The most complex forms are found in the cooperative spiders, characterized by generation overlap, communal nests, food sharing and cooperative parental care. The two unique social pseudoscorpion species are found in South America. These species present a very similar social structure observed in the cooperative spiders, denominated "non-territorial permanent sociality". The present study investigated the natural history and the social behavior of Paratemnoides nidificator, a very common social Atemnidae in the Brazilian Savannah (Cerrado), at field and laboratory, over four years. This pseudoescorpião constitutes large family colonies, characterized by cooperative parental care extended until that the nymphs reach the adult phase, which can culminate in matriphagy. P. nidificator is a sit-and-wait generalist predator, capable to attack and subdue cooperatively preys sixty times heavier than a single individual. The dispersion in this species occurs by two ways: phoresy and colony fission. The Paratemnoides colonies present etarian and sexual division of work, in which individuals of different sex or stage can specialize in specific tasks colony maintenance. This is the first wide study about the natural history and behavior of a social pseudoscorpion. All these information, together, allow a wide comparison of the pseudoscorpions and spiders social organization.