Occurrence and population distribution of Withius aff. piger (Simon, 1878) (Withiidae), in commercial laying hen poultry houses in southern Brazil

Laying hen house settings are favorable sites for the presence of many arthropods, e.g. pseudoscorpions, which are arachnids that are predators of ecological importance and yet are poorly studied. The aim of this study was to investigate the population fluctuation of a pseudoscorpion found in a commercial laying hen house. Samplings were performed weekly, in two commercial laying hen houses (Céu Azul, PR, Brazil, between April and November 2021). Sampling was conducted using Avivet traps attached to the cages. Their content was analyzed in the laboratory. Pseudoscorpions were separated, counted, and individualized into plastic micro-tubes, containing a 70% alcohol solution. The species Withius aff. piger (Simon 1878) (Withiidae) was confirmed in all traps with presence of pseudoscorpions, mainly in August and September, associated to high populations of Dermanyssus gallinae (De Geer 1778) (Dermanyssidae).