On the Chinese species of the genus Intestinarius Kurbatov (Coleoptera, Staphylinidae, Pselaphinae)

Abstract A total of three Chinese species of the genus Intestinarius Kurbatov, 2007 are recognized, among which, two new species are described: Intestinarius guangdongensis sp. n. from Guangdongand Intestinarius longiceps sp. n. from Guizhou. Illustrations of major diagnostic characters are given for all three Chinese species including Intestinarius kuzmini Kurbatov, 2007. A key is included to aid in their identification.


Introduction
Eight species of the genus Intestinarius Kurbatov, 2007 (type species: Batrisodes quinquesulcatus Raffray, 1904) have been so far known from the Southeast Asia: one from Indonesia, two from Laos, three from Malaysia, one from both Singapore and Malaysia and one from China. Intestinarius was thought to be closely allied to Mnia Newton & Chandler, 1989 by certain shared morphological characters (Kurbatov 2007: 282; re-ferring to Mnia see Löbl (1973)) and may be distinguished from Mnia by the presence of well-defined longitudinal sulci on the head and pronotum, by the first antennomere not remarkably elongate, by each elytron with three basal foveae, and by the sternite IV without discal carinae (basolateral incisions in Kurbatov (2007)).
Species of Intestinarius are morphologically similar and the correct identification must be based on the study of male sexual characters. In the present study, we found that characters on female genitalia may also provide a faithful identification.
During several recent collecting trips conducted in South and Southwest China, the authors and their colleagues collected some Intestinarius specimens in Guangdong, Guizhou, and Yunnan Provinces which prove to be two new and one known species. The purpose of this paper is to describe the new species, to provide illustrations of major diagnostic characters and a key for the identification of the so far known Chinese species.

Material and methods
All specimens were collected from the leaf litter of the forest floor by sifting. They were killed with ethylacetate and then dried. Dissections were done in 75% ethanol. The genital organs and other dissected parts were mounted in Euparal (Chroma Geselschaft Schmidt, Koengen, Germany) on plastic slides that were placed on the same pin as the specimen. Photos were taken by a Canon EOS 40D Camera mounted with an MP-E 65 mm Macro Photo Lens or by a Canon G9 Camera mounted on an Olympus CX31 microscope; line drawings were made using Adobe Illustrator CS2.
Slash (/) is used to separate different lines on the same label. The terminology of foveal system follows Chandler (2001).
The following acronyms are used in the text: BL length of body (= hl+pl+el+al) HL maximum length of head, measured from anterior margin of clypeus to posterior base, excluding occiput HW maximum width of head, measured across eyes PL length of pronotum, measured along midline PW maximum with of pronotum EL length of elytra, measured along sutural line EW maximum width of elytra AL maximum length of abdomen AW maximum width of abdomen.
Measurements were made based on a random sample of 45 specimens, unite is in millimeter.
All specimens studied are deposited in the Insect Collection of Shanghai Normal University, Shanghai, China (SNUC).
Description   Male ( Fig. 1). Reddish-brown, maxillary palpi and tarsi lighter. Head, pronotum and elytra covered with long setae. Head (Fig. 3) slightly longer than wide. Clypeus short in dorsal view, roundly arcuate on anterior margin; frons markedly impressed between profoundly raised antennal tubercles; vertexal foveae situated backwards, vertexal sulci extended from vertexal foveae to frons; carinae lateral to the vertexal sulci derived from base of antennal tubercles well-defined; occipital carina reaching posterior margin of frontal impression; postocular margins moderately long, nearly straight, gradually narrowed toward base. Eyes well-developed, each comprised of about 25 facets. Fourth palpomere of maxillary palpi with tuft of dense and fine external setae. Gular carina not conjoint with gular fovea. Antennae as in Fig. 6. Pronotum (Fig. 3) about as long as wide, median longitudinal sulcus extended beyond transverse antebasal sulcus, two lateral longitudinal sulci well-defined, exterior one born from lateral antebasal foveae; two pairs of basolateral foveae and two pairs of antebasal conical tubercles well-defined. Each elytron with three basal foveae and complete sutural stria; discal stria short, reaching less than half of elytral length. Mesotrochanters slightly protuberant on posterior margin, mesotibiae without apical protuberance; metatrochanters modified ( Fig. 12), setose on posterior margin.
Abdomen with tergite IV largest, V-VI about same length and successively narrowed, tergite (Figs 15-16) VII modified, provided with median small round impression, tuft of long setae directed toward posterior margin; tergite VIII as in Fig. 17; sternite VIII as in Fig. 18; sternite IX as in Fig. 19; aedeagus as in Figs 20-22.
Female. Slightly smaller than male; each eye comprised of about 15 facets; maxillary palpi, legs and tergite VII lacking modifications; tergite VIII as in Fig. 39; sternite VIII as in Fig. 40; female genitalia as in Figs 45-46.
Distribution. Known only from the type locality. Etymology. The species is named after its type locality. Ramarks. The modified maxillary palpomere IV of the new species is shared only with I. quinquesulcatus, type species of the genus, described from Singapore and Maylasia; the unmodified male mesotibiae is similar to that of I. orthopygium (Laos); the modified metatrochanters resemble those of I. distorticeps (Jawa), I. quinquesulcatus, I. kuzmini (Yunnan, China), I. orthopygium, I. crassicornis (Laos) and I. longiceps sp. n. (Guizhou, China); the modified tergite VII also occurs in most species of the genus except for I. distorticeps and I. pexatus. Intestinarius guangdongensis may be dintinguished from all its congeners by a combination of the following characters: simple mesotibiae, shape of modified metatrochanters and shape of sternite VIII in male, shape of female tergite and sternite VIII and genital organs of both sexes.

Intestinarius kuzmini
Distribution. Known from Meng-yang and Na-ban-he Nature Reserves of Yunnan Province, Southwest China.
Remarks. Intestinarius kuzmini is similar to its Chinese congeners with respect to the sexually modified tergite VII and metatrochanter. Male of this species may be distinguished by having long apical tooth on mesotibiae, by the shape of modified metatrochanter and by the shape of aedeagus; females may be identified based on the shape of tergite VIII, sternite VIII and genitalia.
Remarks. The new species may be distinguished from all its congeners by the combination of the male secondary sexual characters, viz. the mesotibiae and metatrochanter, the tergites VII-VIII and the sternites VIII-IX, and the shapes of male and female genitalia.

Key to Chinese species of the genus Intestinarius Kurbatov
All the Chinese species are externally very similar, thus, a faithful identification must be based on the dissection of the male and female genital organs combined with certain male secondary sexual characters included in the following key. Male: fourth maxillary palpomere with tuft of dense and short setae on exterior margin; mesotibiae lacking apical protuberance (Fig. 9); aedeagus robust,