A new species of Diplogyniopsis (Acari: Mesostigmata: Diplogyniidae) from Passalidae (Coleoptera) in China and Thailand.

Diplogyniopsis fluctuosumsp. nov. associated with passalid beetles is described based on females from China on undermined passalid beetles, as well as on females and males from Thailand on Aceraius helferi (Coleoptera: Passalidae). The species represents the second known species of Diplogyniopsis Trägårdh, prompting us to redefine the genus diagnosis. [ABSTRACT FROM AUTHOR]