New species of the genus Plonaphacarus (Oribatida, Steganacaridae) from China

Two new species belonging to the family Steganacaridae are described from Oriental part of China: Plonaphacarus luxiensis sp. nov. differs from Plonaphacarus concavus Liu, Wu & Chen, 2011 by the long and stout interlamellar and lamellar setae, lateral prodorsal carinae absent, exobothridial setae vestigial, anterodorsal part of notogaster not concave dorsally, notogastral setae c1 and anal setae short and spiniform, setae c1 positioned close to anterior border of notogaster and setae d on femora I distanced to distal end of segment; Plonaphacarus hailingensis sp. nov. differs from congeneric species by the presence of heterotrichy of notogastral setae, in which setae c1, c2 and c3 long and flagellate distally, prodorsum with median crista and posterior furrows, sensilli long and setiform, and rostral setae short, spiniform and semi-erect. A key to all known species of Plonaphacarus from China are provided to facilitate identification of this group.