Abstract
Cosmolaelaps paulista n. sp. is described based on specimens collected from litter of the Atlantic Forest (Mata Atlântica) of the State of São Paulo, in southeastern Brazil. Reared on Tyrophagus putrescentiae (Schrank), at 25 °C, development from egg to adult required 8.6 ± 0.9 days, the total number of eggs laid was 95.4 ± 25.0 per female, and the population increase capacity was relatively high, as suggested by the calculated valueof rm (0.217 female per female per day).