Diversity of edaphic rhodacaroid mites (Acari: Mesostigmata: Rhodacaroidea) in natural ecosystems in the state of Sao Paulo, Brazil

This study was conducted to evaluate the diversity of rhodacaroid mites in litter and soil samples from "Mata Atlantica" and "Cerrado", e ecosystems of the state of Sao Paulo, Brazil. A total of 969 adult rhodacaroids were collected, 913 in the Mata Atlantica and 56 in the Cerrado. Representatives of three rhodacaroid families were from: Ologamasidae, Rhodacaridae and Digamasellidae. Most numerous groups were ologamasids in the Mata Atlantica and rhodacarids in the Cerrado. Mites from both ecosystems represented 12 genera of Ologamasidae, two of Rhodacaridae and one of Digamasellidae. A total of 13 genera were found in litter samples and seven in soil samples of Mata Atlantica. The most common genera in this ecosystem were Neogamasellevans Loots & Ryke and Ologamasus Berlese in litter, and Rhodacarus Oudemans in soil samples. Thirty-one morphospecies were recovered, the most abundant being Rhodacarus sp.1, Neogamasellevans sp.1 and Neogamasellevans sp.6. Three rhodacaroid genera were found in each substrate of Cerrado, the most abundant being Rhodacarus and Rhodacarellus Willman. Of the five morphospecies found in this ecosystem, the most abundant was Rhodacarus sp.1. Morphospecies collected in Mata Atlantica displayed a higher equitability in frequency of occurrence than those of Cerrado, especially in litter samples. The plant species sampled in Mata Atlantica comprised two distinct groups in terms of the rhodacaroid morphospecies associated with them: 1) Astrocaryum aculeatissimum (Schott), Bactris setosa Mart. and Attalea dubia (Mart.); and 2) Syagrus romanzoffiana (Cham.) and Euterpe edulis Mart.