Four new species and additional records of Domene and Lathrobium from the Dayao Mountains, southern China

Abstract Material of the paederine genera Domene Fauvel, 1873 and Lathrobium Gravenhorst, 1802 from the Dayao Mountains, southern China, is examined. Eight species are identified, three of them described previously and five undescribed. Four species are described and illustrated for the first time: Domene hei Peng & Li, sp. n., Lathrobium jinxiuense Peng & Li, sp. n., Lathrobium kuan Peng & Li, sp. n. and Lathrobium leii Peng & Li, sp. n. One probably undescribed species of Lathrobium remains unnamed.

Covering an area of 249.07 km 2 , the Dayao Mountains are situated in central Guangxi, southern China. The highest peak is the Shengtang Shan at 1,979 m. According to Deng (1984) two vertical zones of forest vegetation can be distinguished: an evergreen broad-leaved forest zone at elevations below 1,300 m and a mixed broadleaved and coniferous forest zone at altitudes above 1,300 m.
In 2011 and 2014, Jia-Yao Hu, Zi-Wei Yin, Xiao-Bin Song, Yi-Ming Yu, Zhu-Qi Yan and the first author made two collecting trips to Dayao Mountains, where they collected numerous Domene and Lathrobium specimens. Eight species were identified, four of which are described for the first time.

Material and methods
The following abbreviations are used in the text, with all measurements in millimeters: Body length (BL) from the anterior margin of the mandibles (in resting position) to the abdominal apex; length of forebody (FL) from the anterior margin of the mandibles to the posterior margin of the elytra; head length (HL) from the anterior margin of the frons to the posterior margin of the head; head width (HW): maximum width of head; length of antenna (AnL); length of pronotum (PL) along midline; maximum width of pronotum (PW); elytral length (EL) at the suture from the apex of the scutellum to the posterior margin of the elytra (at the sutural angles); length of aedeagus (AL) from the apex of the ventral process to the base of the aedeagal capsule.
The type material is deposited in the Insect Collection of Shanghai Normal University, Shanghai, China (SNUC).  1C) somewhat narrower than head, widest in the middle; lateral margins convex in dorsal view; punctation similar to that of head; midline with rudiment of a fine glossy line.

Domene
Each elytron with more or less irregular longitudinal narrowly elevated ridges; suture elevated in posterior two thirds; macropunctation coarse and partly somewhat seriate; interstices with irregular micropunctation. Hind wings reduced. Protarsomeres I-IV distinctly dilated.
Abdomen with fine and dense punctation on tergites III-VIII; posterior margin of tergite VIII weakly convex ( Fig. 2A); interstices with distinct microreticulation; posterior margin of tergite VII with palisade fringe. Comparative notes. Based on more or less irregular longitudinal elevations of elytra, the derived morphology of the aedeagus and particularly on the shapes and chaetotaxy of the male sternites VIII, D. hei belongs to the D. scabripennis species group. It is distinguished from other species of this group by the coloration of legs, the fine glossy line on the pronotum, the shape of the ventral process of the aedeagus and the slender sclerotized structure in the female genital segments. For illustrations of the species of the D. scabripennis species group see Assing (in press a) and Assing and Feldmann (2014).
Etymology. The species is dedicated to Wei-Jun He, specialist of Phasmatodea, who supported us on our field trips.
Distribution and natural history. The type locality is situated in the Shengtang Shan to the southwest of Jinxiu, central Guangxi. The specimens were sifted from leaf litter in a rhododendron forest at altitudes of 1,200-1,400 m, together with Lathrobium shengtangshanense Peng & Li, 2012.  Pronotum nearly parallel-sided; punctation similar to that of head; impunctate midline broad; interstices without microsculpture.
Abdomen with fine and moderately dense punctation, that of tergite VII somewhat sparser than that of anterior tergites; interstices with shallow microsculpture; posterior margin of tergite VII without palisade fringe; tergite VIII without sexual dimorphism, posterior margin (Fig. 5A) obtusely angled in the middle.
Male. Sternites III-VI unmodified; sternite VII ( Fig. 5D) with very shallow postero-median impression, this impression without distinctly modified setae, posterior Comparative notes. The new species resembles L. maoershanense Peng & Li, 2012 in habitus and the similarly derived morphology of the aedeagus, but differs from this species by the smaller posterior excision of the male sternite VIII, the more slender ventral process of the aedeagus and the shape of the female tergite VIII. For illustrations of L. maoershanense see Peng et al. (2012).
Etymology. The specific epithet is derived from Jinxiu, where the type locality is situated.
Distribution and natural history. The type locality is situated in Qigongli to the north of Jinxiu, central Guangxi. The specimens were sifted from leaf litter and humus in a beech forest at an altitude of 1,300 m, together with L. dayaoshanense Peng & Li, 2012.  Habitus as in Fig. 4B. Body dark brown, legs and antennae brown. Head approximately as long as broad; punctation coarse and moderately dense, somewhat sparser in median dorsal portion; interstices with shallow microreticulation; eyes small and composed of approximately 30 ommatidia.
Pronotum nearly parallel-sided; punctation similar to that of head; impunctate midline moderately broad; interstices glossy and without microsculpture. Elytral punctation dense and well-defined. Hind wings completely reduced. Protarsi without sexual dimorphism.
Abdomen with fine and dense punctation, that of tergite VII sparser than that of anterior tergites; interstices with distinct microsculpture; posterior margin of tergite VII without palisade fringe; tergite VIII without sexual dimorphism, posterior margin (Fig. 6A) obtusely angled in the middle.
Male. Sternites III-VI unmodified; sternite VII ( Fig. 6D) with very shallow posteromedian impression, this impression with weakly modified setae, posterior margin nearly truncate; sternite VIII ( Fig. 6E) with very narrow median impression posteriorly, this impression with numerous short dark setae, posterior excision V-shaped and symmetrical; aedeagus as in Figs 6F, G; ventral process asymmetrical, broad and furcate; internal sac with a long strong sclerotized spine and a shorter weakly sclerotized spine.
Comparative notes. Based on the modifications of the male sternite VIII, the furcate ventral process of the aedeagus, the presence of long sclerotized spines in the internal sac of the aedeagus, and the divided female tergite IX, Lathrobium kuan belongs to the L. fissispinosum group, which was previously known from Shaanxi, Gansu, Hubei, Guizhou and Sichuan. The new species is distinguished from the other representatives of this group by the chaetotaxy and shapes of the male sternites VII and VIII, the strongly asymmetrical ventral process and the presence of two (rather than one) sclerotized spines in the internal sac of the aedeagus. For illustrations of the species of the L. fissispinosum group see Assing (2013b, in press b) and Peng et al. (2013bPeng et al. ( , 2014b. Etymology. The specific name is the Chinese adjective "kuan" (broad). It refers to the broad ventral process of the aedeagus of this species, when compared with the other species known from Dayao Mountains.
Distribution and natural history. The type locality is situated in the Shengtang Shan to the southwest of Jinxiu, central Guangxi. The specimens were sifted from leaf litter in a beech forest at an altitude of 1,160 m. Head approximately as long as broad; punctation coarse and moderately sparse, distinctly sparser in median dorsal portion; interstices with shallow microreticulation; eyes small and composed of approximately 35 ommatidia.

Lathrobium leii
Pronotum with weakly convex lateral margins in dorsal view; punctation similar to that of head; impunctate midline broad; interstices without microsculpture.
Abdomen with fine and moderately dense punctation, that of tergite VII somewhat sparser than that of anterior tergites; interstices with shallow microsculpture; posterior margin of tergite VII without palisade fringe; tergite VIII without sexual dimorphism, posterior margin (Fig. 7A) asymmetricalally obtusely angled.
Male. Sternites III-VI unmodified; sternite VII ( Fig. 7D) with truncate posterior margin and without distinctly modified setae; sternite VIII ( Fig. 7E) with very shallow postero-median impression, this impression with short dark setae posteriorly, posterior excision small and weakly asymmetrical; aedeagus as in Figs 7F, G; ventral process long and slender; dorsal plate with very long moderately sclerotized apical portion and short weakly sclerotized basal portion; internal sac with a long sclerotized spine.
Comparative notes. Based on the different general morphology of the aedeagus, L. leii represents a different lineage than the other species recorded from Dayao Mountains. It is additionally distinguished from them by smaller body size, yellowish brown legs, the chaetotaxy of the male sternite VIII, and a slender aedeagus with a long sclerotized spine.
Etymology. The species is dedicated to Yu-Yang Lei, who supported us on our field trips.
Distribution and natural history. The type locality is situated in the Shengtang Shan to the southwest of Jinxiu, central Guangxi. The specimens were sifted from leaf litter and humus in a rhododendron forest at an altitude of 1,300 m, together with L. shengtangshanense. Comment. The above micropterous female represents an undescribed species distinguished from the other species known from Dayao Mountains by somewhat smaller body size, the slender pronotum and the female secondary sexual characters.