Two new and a newly recorded species of the genus Pergalumna (Acari, Oribatida, Galumnidae) from China

Two new species, Pergalumna clava n. sp. and Pergalumna pilosus n. sp., and a newly recorded species, Pergalumna amamiensis Aoki, 1984 of oribatid mites are described and illustrated from China. Pergalumna clava n. sp. is different from most known species of Pergalumna in the dorsosejugal suture complete; developed four pairs notogastral porose areas, Aa transverse irregular wedge; short interlamellar seta and bothridial seta clavate. Pergalumna pilosus n.sp. different from most known species of Pergalumna in the dorsosejugal suture complete; Aa porose area transverse irregular wedge; longer interlamellar barbed; median pore and postanal porose area present.


Introduction
Pergalumna was proposed by Grandjean, 1936 with Oribata nervosa Berlese, 1914 as type species. The genus is one of the largest genera of the family Galumnidae, which comprises two subgenera, 169 species and 14 subspecies, and collectively have a cosmopolitan distribution (Ermilov and Klimov, 2017; Subías, 2004, updated 2020. At present, 15 species and 4 subspecies of Pergalumna were recorded in China (Chen et al., 2010; Zheng et al., 2019; Subías, 2020.
During taxonomic identification of oribatid mites from China, we found two new species, Pergalumna clava n. sp. and Pergalumna pilosus n. sp. and a newly recorded species, Pergalumna amamiensis Aoki, 1984. The main goal of this study is to describe the new species, give a supplementary description to Pergalumna amamiensis and illustrate these species.

Material and methods
Samples, such as, deciduous leaves, moss, humus and grassland soil were collected by a soilcorer. Mites were extracted by using Tullgrenfunnels, and then they were immersed in lactic acid and placed in DHG Series Heating and Drying Oven "DHG9013A" at 50°C for 8 to 72 hours, the time required varies depending on the size. Afterwards, the transparent mites were placed on a concave slide with glycerol for measurement and observation, which were made with a camera lucida using a Nikon digital microscope imaging system "NIKON NIE+DSRI2+NISAR". All body measurements are presented in micrometers. The body length was measured in lateral view, from the tip of the rostrum to the posterior edge of the ventral plate, to avoid discrepancies caused by different degrees of notogastral distension. Notogastral width refers to the maximum width in dorsal aspect. Lengths of body setae were measured in lateral aspect. Formulas for leg setation are given in parentheses according to the sequence trochanterfemurgenutibiatarsus (famulus included). Formulas for leg solenidia are given in square brackets according to the sequence genutibiatarsus.
The specimen (for scanning electron microscopy) is treated to a fully dehydrated state and dried, specimens were coated film by used rotation goldplatedpalladium alloy membrane, observed under the JEOL JCM6000 scanning electron microscopy.
General terminology used in this paper follows that of F. Grandjean (see Travé and Vachon, 1975 for a complete list of Grandjean's references, Norton &Behan-Pelletier, 2009 for overview, andKlimov, 2017 for a concise overview of the general morphology of Galumnoidea).

Material examined
Holotype (

Type deposition
The holotype and 7 paratypes are deposited in the Institute of Entomology, Guizhou University, Guiyang, China (GUGC) (Zhang 2018). 46 paratypes are deposited in the Guizhou Provincial Center for Disease Control and Prevention, Guiyang, China.

Etymology
The name of the new species comes from the Latin word "clava" meaning "clavate" which means that the new species bothridial seta clavate.

Type deposition
The holotype and 16 paratypes are deposited in the Institute of Entomology, Guizhou University, Guiyang, China (GUGC). 10 paratypes are deposited in the Guizhou Provincial Center for Disease Control and Prevention, Guiyang, China.

Etymology
The name of the new species comes from the Latin name "pilosus" meaning "hairy" which refers to the comparable long cilia on rostrum, lamellar and interlamellar setae of the new species.
Legs - (Figure 11). All legs tridactylous, median claw distinctly thicker than lateral    Aoki, 1984. Leg Tr Fe Ge Ti Ta Note: Roman letters refer to normal setae, Greek letters to solenidia (except ɛ = famulus). Single prime (') marks setae on the anterior and double prime (") setae on the posterior side of a given leg segment. Parentheses refer to a pair of setae. Remarks This species was originally described by Aoki (1984) from Japan, but the original descrip tion was brief and not completely illustrated, so we gove a supplementary description and illustrations. Apart from the lacking characteristics, the Chinese specimens differ from the Japanese specimens by the rostral, lamellar, interlamellar and bothridial setae which are slightly barbed. Hence, based on these supplementary data, the main characters of P. amamiensis are: body size: 540-680×390-490, body surface densely foveolate granules; rostrum pointed; lamel lar and sublamellar lines present; rostral, lamellar and interlamellar setae developed, setiform, slightly barbed; bothridial setae spindleshaped, stalk slender and head slightly incrassate and spiculate; dorsosejugal porose areas and dorsosejugal suture present; four pairs of notogastral porose areas, Aa transversely wedgeshaped, A1 rounded, A2 and A3 oval; median pore and postanal porose area present; epimeral setal formula 1012; ventral setae, genital setae, epimeral setae, anogenital and adanal setae represented by microsetae; all legs tridactylous, leg setae not modified.