Lathrobium songi Peng and Li

Peng, Zhong, Li, Qi-Li, Shen, Liang & Gu, Fu-Kang, 2015, On the Lathrobium fauna of the Donggong Mountains, eastern China, Zootaxa 3905 (2), pp. 245-263 : 252-254

Lathrobium songi Peng and Li , new species

( Figs 6 A, 7)

Type material. HOLOTYPE: ♂, labeled ‘ China: Zhejiang Prov., Qingyuan County, Baishanzu Natural Reserve, 27°45'14''N 119°11'55''E, 1560–1750 m, 01.V.2014, Peng, Song, Yan & Yu leg.’ ( SNUC). Paratypes: 1 ♂, 1 ♀, same label data as holotype ( SNUC); 2 ♂♂, same data, but ‘ 27°45'26''N 119°12'08''E, 1730 m, 02.V.2014 ’ ( SNUC); 1 ♂ [teneral], same data, but ‘ 1250–1650 m, 21.VIII.2004, Hu, Tang & Zhu leg.’ ( SNUC); 1 ♀, same data, but ‘ 27°45'N 119°12'E, 1500 m, 23.IX.2008, Tang & Zhu leg.’ ( SNUC).

Description. Measurements (in mm) and ratios: BL 9.45–9.73, FL 4.44–4.84, HL 1.15–1.22, HW 1.26–1.33, AnL 2.56–2.67, PL 1.52–1.68, PW 1.30–1.42, EL 0.78–0.92, AL 1.54–1.62, HL/HW 0.90–0.93, HW/PW 0.94–0.97, HL/PL 0.73–0.76, PL/PW 1.16–1.19, EL/PL 0.51–0.55.

Habitus as in Fig. 6 A. Body dark brown, legs and antennae brown.

Head transverse, weakly dilated posteriorly; punctation coarse and moderately sparse, distinctly sparser in median dorsal portion; interstices with shallow microreticulation. Eyes moderately small and composed of approximately 50 ommatidia.

Pronotum with weakly convex lateral margins in dorsal view; punctation similar to that of head; impunctate midline broad; interstices glossy and without microsculpture.

Elytral punctation dense, shallow and ill-defined. Hind wings completely reduced. Protarsi without appreciable sexual dimorphism, distinctly dilated.

Abdomen with fine and moderately dense punctation, that of tergite VII somewhat sparser than that of anterior tergites; interstices with very shallow microsculpture; posterior margin of tergite VII without palisade fringe; tergite VIII with distinct sexual dimorphism.

Male. Posterior margin of tergite VIII truncate; sternite III unmodified; sternite IV ( Fig. 7 D) with dense dark setae in very large postero-median impression; sternite V ( Fig. 7 E) similar to sternite IV, but with longer setae in smaller impression and at middle of posterior margin with cluster of numerous point-like setae; sternite VI ( Fig. 7 F) without postero-median impression and at middle of posterior margin with cluster of several point-like setae; sternite VII ( Fig. 7 G) strongly transverse, with shallow median impression posteriorly, this impression without distinctly modified setae, posterior margin broadly concave; sternite VIII ( Fig. 7 H) with asymmetric and extensive median impression posteriorly, this impression with numerous modified stout blackish setae, posterior excision deep and asymmetric; aedeagus as in Figs 7 I, J, ventral process asymmetric, dorsal plate large, with broad apical portion and thin, short basal portion; internal sac with three sclerotized spines of different shapes.

Female. Posterior margin of tergite VIII ( Fig. 7 A) pointed in the middle; sternite VIII as in Fig. 7 B, posterior margin distinctly convex and somewhat truncate in middle; tergite IX ( Fig. 7 C) with short antero-median portion and slender postero-lateral processes; tergite X ( Fig. 7 C) 3.9 times as long as antero-median portion of tergite IX.

Comparative notes. As can be inferred from the similarly derived chaetotaxy of the male sternite VII, the similarly derived structure of the aedeagus, as well as from the similarly female tergites IX and X, L. songi is allied to L. tangi Peng & Li, 2012 . It differs from L. tangi by the more slender body, the glossy interstices on the pronotum, the absence of point-like setae on the male sternite IV, the longer modified setae on the male sternite V, the presence of point-like setae on the male sternite VI, the shape and chaetotaxy of the male sternite VIII, the somewhat more slender ventral process and longer dorsal plate of the aedeagus, as well as the shape of the female sternite VIII. For illustrations of L. tangi see Peng et al. (2012a).

Distribution and biological notes. The type locality is situated in the Baishanzu Natural Reserve to the north of Qingyuan, southern Zhejiang. The specimens were sifted from leaf litter and humus in beech forests with bamboo at altitudes between 1250 and 1750 m, together with L. immanissimum , L. baishanzuense , L. obstipum and L. zhui . One specimen collected in August is teneral.

Etymology. The species is named for Xiao-Bin Song, who collected some of the type specimens.

Figures

FIGURE 6. Habitus of Lathrobium spp., A — L. songi; B — L. yui; C — L. fengyangense. Scale bars: 1.0 mm.

FIGURE 7. Lathrobium songi. A — female tergite VIII; B — female sternite VIII; C — female tergites IX – X. D — male sternite IV; E — male sternite V; F — male sternite VI; G — male sternite VII; H — male sternite VIII; I — aedeagus in ventral view; J — aedeagus in lateral view. Scale bars: 0.5 mm.