One new species and three newly recorded species of Neopallodes Reitter from China (Coleoptera, Nitidulidae, Nitidulinae)

Abstract One new species of the sap beetle genus Neopallodes, N. nigrescenssp. nov., is described and illustrated. New information on the distribution and illustrations of three species, N. dentatus Kirejtshuk, 1994, N. falsus Grouvelle, 1913 and N. vietnamicus Kirejtshuk, 1987, which are newly recorded from China, are also supplemented. A key to species of the genus Neopallodes from China is provided.


Introduction
The genus Neopallodes Reitter, 1884 was proposed for three species from Japan (Reitter 1884). Grouvelle (1892Grouvelle ( , 1902Grouvelle ( , 1903 later described another three species in this group although this taxon was treated as a synonym by Grouvelle (1913a). However, C.T. Parsons (1943) regarded Neopallodes as a valid genus. Five species from Japan and one species from Chejudo Island, Korea, were recorded by Y. Kurosawa et al. (1985) and M. Chûjô and C.E. Lee (Chûjô and Lee 1992), respectively. Kirejtshuk (1987Kirejtshuk ( , 1994Kirejtshuk ( , 2011 described 16 species and revised the Palaearctic and Indo-Malayan species. Later, Kirejtshuk (1992) distinguished Neopallodes from Pallodes Erich-son, 1843, based on the exposed male anal sclerite from under the transverse pygidial apex, and proposed some additional diagnostic characters for these taxa. Twenty-one species previously placed in Pallodes Erichson, 1843 by Grouvelle (1896Grouvelle ( , 1906 and Reitter (1877) were also transferred to Neopallodes by Kirejtshuk (1994). Kirejtshuk (2008) gave a complete species checklist of Neopallodes, including 40 East Asian species (mostly in the Palaearchearctic or East-Chinese Province of the Palearctic Region, Indo-Malayan, and Malgassy regions.
Prior to our studies, only three species, Neopallodes hilleri Reitter, 1877, N. inermis Reitter, 1884, and N. vicinus Grouvelle, 1892, have been recorded from China (Kirejtshuk 1992, 1994. Here, we describe one new species and newly record three species from China. A key to the Chinese species of Neopallodes is presented.

Materials and methods
All materials for this study are deposited in the Entomological Museum of Northwest A&F University (NWAFU), Yangling, China. Most samples were preserved in 99% ethanol, although some were preserved as dried specimens. All photographs were taken using a Leica M205A microscope with a Leica DFC camera, and image stacking was done using LAS (Leica Application Suite) V3.7. Images were retouched with Adobe Photoshop CS6. Illustrations were drawn using Adobe Illustrator CS4.
Morphological terminology follows Kirejtshuk (1994Kirejtshuk ( , 2011. Body length measures from the anterior edge of clypeus to the posterior apex of pygidium; body width refers to the maximum width of elytra.

Remarks.
Congeners of Neopallodes are mycophagous, and their adults are associated with the sporocarps and thalli of Agaricaceae (Basidiomycetes). So far, larvae are known to be found on the mycelia of these fungi or in their fruiting bodies (Hayashi 1978;Kirejtshuk 1994;Leschen 1999;Yamashita and Hiji 2007). Yunnan Province accounts for 90% of the wild mushroom species in China (Liu 2014), and, the species in this genus so far collected in China are all distributed in Yunnan Province. This suggests that the abundance of fungi may potentially harbor undiscovered species of this genus. Outer apical angle of protibia without distinctly raised tooth ( Fig. 9); scutellum subtriangular with round apex (Figs 1, 3); prosternum slightly carinate with moderately subflattened process slightly widened at subtruncate apex and not bend to mesoventrite between mesocoxa; abdominal ventrite 1 much longer than hypopygidium ( ; antennal club narrower than prosternal process; antennal club distinctly shorter than antennomeres 2-8 together, antennomere 11 wider than long, antennomere 9 shorter than antennomere11 (Fig. 8); metaventrite with fine punctures in the middle and large, sparse punctures laterally (Figs 2, 4)  Antennal club longer than antennomeres 2-8 together; elytra with longitudinal rows of punctures not quite regular at basal third; elytra with large, blackish spots at humeral angles; pronotum with two subcircular, blackish spots; protibia with strongly raised tooth. (Fig. 20) (Kirejtshuk, 1987) -Antennal club subequal in length with antennomeres 2-8 together; elytra with clearly longitudinal rows of punctures, including their basal third; elytra without spots at humeral angles; pronotum with two subtriangular, blackish spots; protibia with moderately raised tooth. (Fig.19) .. Description. Body size (♂): length 2.7-3.7, width 2.1-3.1 mm. Body: Body shiny, dorsum glabrous, abdomen with sparse and inconspicuous hairs, moderately convex dorsally and ventrally. Dorsal and ventral surface blackish with antennae and tarsi lighter, or dorsal surface blackish with elytra brightly brownish orange, ventral surface yellowish brown with metaventrite darker (Figs 1-4).

Key to the species of
Dorsal habitus: Head somewhat depressed with medium-sized eyes, punctures larger than eye-facets. Lobes of labrum clearly exposed with short excision (Fig. 5). Mandible exposed from under lobes of labrum, with four small teeth on apical edge (Fig. 15). Length of antenna subequal with head width, scape subcylindrical, slightly curved and about 1.5 times as long as wide, pedicel approximately subcylindrical and nearly 1.5 times as long as wide, antennomere 3 narrowed basally, antennomeres 3 and 4 longer than wide, antennomere 4 longer than antennomere 5, each of antennomeres 5-8 wider than long, antennal club compact and asymmetrical, with length nearly 0.6 times of total antennal length, antennomere 11 shorter than antennomeres 9-10 together (Fig. 8). Pronotum widest at base and arcuately narrowed to apex; anterior edge deeply emarginate; posterior edge vaulted with clear projection covering base of scutellum, anterior and posterior angles blunt; surface with punctures round, slightly smaller than eye-facets and separated by 2.7-5.7 puncture diameters; interspaces smooth to alutaceous. Scutellum subtriangular with round apex, with punctures scattered and separated by 0.7-1.9 puncture diameters. Elytra about 0.9 times as long as wide together, widest at basal 1/3; surface with regular longitudinal rows of large punctures separated by 0.8-1.3 diameters in rows; rows separated from each other by 5.3-6.9 puncture diameters; interspaces microreticular, between rows of large punctures with irregular row of very fine and sparse punctures. Pygidium markedly wider than long, subtruncate at apex and with dense punctures subequal to those on pronotum (Fig. 6). Anal sclerite slightly wider than long (Fig. 7).
Ventral habitus: Terminal maxillary palpomere elongate and subconical (Fig. 16). Terminal labial palpomere narrowing apically. Mentum pentagonal with sparse, large punctures along posterior edge (Fig. 13). Antennal grooves strongly convergent behind mentum. Prosternum convex medially, with moderately subflattened process, slightly widened at subtruncate apex, and about 1.7 times as wide as scape. Mesoventrite moderately carinate. Metaventrite with finer punctures in middle and coarser punctures laterally. Metepisternum somewhat narrower than antennal club and with distinct, large punctures. Epipleura almost 0.6 times as wide as antennal club long. Abdominal ventrite 1 longest, about 1.6 times as long as hypopygidium and 2.1 times longer than each of ventrites 2-4. Hypopygidium rounded at apex. Submesocoxal line almost rectilinearly deviating from posterior edge of mesocoxal cavity (Figs 2, 4). Distance between metacoxae more than three times as great as that between procoxae, and about twice as great as that between mesocoxae.
Protibia artcuately curved, about as wide as antennal club, with rounded outer apical angle and with apical angle round (Fig. 9); meso-and metatibiae almost subtriangular and slightly narrower than protibia, both with rows of dense setae along outer edge. Femora 1.8 times as wide as corresponding tibiae. Metatarsus shorter than corresponding tibia.
Male genitalia: Tegmen narrow, strongly sclerotized and rounded apically, about 4.3 times as long as wide, with short setae disposed along middle of tegmen and forming an X-like figure; also with long setae along sides and at apex (Fig. 10). Penis trunk about 2.1 times as long as wide and 0.4 times long as tegmen, with apex widely rounded and with two wide apical lobes narrowed apically (Fig. 11).
Variability. Some variation is observable in coloration and punctures. The holotype and paratypes from Chuxiong City, Zixi Mountain, and Qujing City, Yehuagou (all Yunnan Province) are subunicolorous black, while the paratypes from Dali City, Cangshan Mountain, and Qujing City, Junzi Mountain (all Yunnan Province) and from Bijie City, Shangdi Mountain (Guizhou Province) are blackish with brightly brownish elytra.
Diagnosis. Neopallodes nigrescens can be distinguished from other species of the genus Neopallodes by its unique body color (dorsal surface blackish or with elytra brightly brownish orange), elytra with regular longitudinal rows of large punctures and not quite regular longitudinal rows of small punctures arranged alternately and tegmen with short setae forming an X-like figure. This taxon is similar to N. inermis, but differs from it in: antennal club distinctly shorter than antennomeres 2-8 combined; metaventrite with fine punctures in the middle and with large, sparse punctures laterally; tegmen with short setae forming an X-like figure; penis trunk with round apex. Name derivation. The specific epithet is derived from the Latin word "nigrescens" (= blackening) referring to the color of dorsal surface of most specimens. Schrock (Emporia State University, USA) for proofreading of the manuscript and giving us with valuable advice before submission. We also greatly appreciate the members of our lab for helping collect specimens. In addition, we thank the anonymous reviewers who have helped to improve the manuscript.