Neolucanus nitidus ( Saunders, 1854 )

Qian Zhang, Yang Ge, Yuanyuan Wu & Xia Wan, 2016, Taxonomic notes on some species of Neolucanus Thomson (Coleoptera: Lucanidae) from China, Zoological Systematics 41 (2), pp. 195-206 : 201-204

Neolucanus nitidus ( Saunders, 1854) (Figs 13–18, 35–38)

Odontolabis nitidus Saunders, 1854 . Trans. Ent. Soc. Lond (N. S.., 3(2): 47.

Neolucanus nitidus: Leuthner, 1885 . Trans. Zool. Soc. Lond., 11: 427.

Neolucanus nitidus nitidus: Mizunuma & Nagai, 1994 . The Lucanid Beetles of the World: 128, pl.19.

Length about 36.0–45.0 mm (including mandibles). Width 15.0–17.0 mm (Figs 13–18). Surface. Dark and shiny, elytra more shiny than other parts. Main surface smooth, small punctures presented on mandibles, the surrounding of eyes. Legs with large and dense punctures. Head. Almost rectangular, gloomy, 2.0–3.0 times wider than long. Anterior margin at middle concaved, with forming a large, triangularly frontal depression in male, that of female much smaller and shallow.

Vertex slightly raised. Male mandibles. Relatively straight, about 1.0–1.2 times the length of head in large male, but shorter in small male. The apex sharp, slightly curved inwards. A large, upwardly erected sub-apical tooth presented on the upper mandibular margin. Other 5–6 small blunt teeth serrated along the lower mandibular margin. Female mandibles. Almost triangular, shorter than the length of head, covering with punctures; the apex sharp and curved inwards; the upper mandibular margin without sub-apical tooth, the lower mandibular margin with 2–3 blunt teeth. Eyes. Relatively small, unproduced, completely divided into the upper and lower part by the canthi. Canthi slightly laminated and expanded, narrowly sub-rectangular with a bluntly rounded apex angle in male, almost semicircular in female. Post-ocular margins little produced, slightly swollen. Mentum. Almost semicircular, anterior angle rounded, covering with long yellow brown hairs; that of female semicircular, no hairs presented except for the distal margin, but with a pair of ridges extended from anterior angle to the middle part of mentum. Labrum. Small and triangular in male; almost rectangular with a small projection on the distal margin at middle in female. Antennae. Sexually dimorphic, longer and stronger in male. Club 3-segmented, terminal segment totally pubescent, other 2 segments partially pubescent. Scape slightly curved, pedicel almost symmetrical; the 3rd, 4th, 5th segment almost equal, the 7th segment with 4–5 apical setae. Pronotum. Transverse, 1.7–2.0 times wider than long, about 1.6–2.4 times the length of head. Disc strongly convex. Anterior margin sinuated, quite gently projected at middle. Front angles blunt. Lateral margins slightly divergent on 4/5 anteriorly, then gently convergent on 1/5 posteriorly and meet the posterior margins. Hind angles sharp. Scutellum. Wider than long, blunt heart-shape, with several small punctures. Elytra. Dark, very shiny and convex; 1.25 times longer than wide, almost as wide as that of pronotum. Wings. Fully developed. Legs. Long and stout. Front tibiae narrow at base, strongly expanded and forked at apex, with 3–6 sharply small lateral teeth; spurs sub-cylindrical and curved, short in male, relatively longer in female. Middle and hind tibiae no lateral tooth presented except for spines at apex. Aedeagus (Figs 35–38). BP slender, about as long as the length of PA; the 2/3 proximal part closed to PA broad and the 1/3 distal part blunt. PA relatively Figures 25–34. Neolucanus spp., genitalia. 25–28. N. guangxi , aedeagus. 29. N. guangxi , female genitalia. 30–33. N. swinhoei hengshanensis , aedeagus, confirmed synonym of N. imitator . 34. N. nitidus , female genitalia. 25, 30. Dorsal view. 26, 31. Lateral view. 27, 32. Ventral view. 28, 33. PES. Scale bars = 1 mm.

short, the apex rounded from the dorsal and ventral view, but slightly sharp from the lateral view. ML distinctly asymmetric, broad, the left lobe little longer than the right one. PES (Fig. 38) very stout, about 2.0 times the total length of BP+PA; mainly outer surface of PES smooth and membranous, densely covering with short dense dark brown hairs from the middle to the apical part. Female genitalia (Fig. 34). HS strongly sclerotized, the anteriorly 4/5 part plate-liked, rather broad, almost rectangular with little rounded distal margin; the posteriorly 1/5 part stick-liked, thin and slightly oblique. AG pale, slender. MO yellow brown, short, stout. BC very long, stout, tubiform and longitudinally folded. SD dark brown, joining in BC and distinctly expanded. S situated at the apex of SD, bulb–shaped symmetrically with expanded apex. SG absent.

Type material examined. Holotype of Neolucanus nitidus , ♂ (Figs 17–18), in OXUM, labelled: nitidus, Saunders (handwritten yellow label) / type, col. 382, Odontolabris nitidus Saund., Hope Dept. Oxford.

Figures 35–42. Neolucanus spp., aedeagus. 35–38. N. nitidus . 39–42. N. pallenscens . 35, 39. Dorsal view. 36, 40. Lateral view. 37, 41. Ventral view. 38, 42. PES. Scale bars = 1 mm.

Additional material examined. China, Fukien, Kuatun, 11 August 1946, 1♂ 1♀, leg. Tschung Sen ( MZUF). Anhui, Mt. Huangshan, alt. 700–1 0 0 0 m, 17–20 August 1978, 12 ♂1♀, leg. Shuyong Wang; Zhejiang, West Mt. Tianmushan, Kaishan Laodian, 3 August 2010, 3♂ 1♀, leg Kai Shi. ( MZAFU); Zhejiang, Mt. Tianmushan, Sanmutian, 1♂, 5 August 2011, leg. Qian Zhang. Fujian, Mt. Wuyishan, 11 August 2009, 2♂, leg. Xiaoyan Hu and Fang Zhong; Mt. Wuyi, 13 August 2012, 1♂, leg. Yuyan Cao ( MAHU).

Distribution. China (Anhui, Jiangxi, Zhejiang, Fujian).

Remarks. Holotype of Neolucanus nitidus is a medium-sized male without mandibles in OXUM, as Saunders wrote that “mandibles wanting in all the specimens sent home”. In the field, N. nitidus can be easily recognized by its shiny dark body color, short and stout mandibles and narrowly subrectangular canthus. However, there are wrong species diagnoses in the two widely used books published by Mizunuma & Nagai (1994) and Fujita (2010). In the former book, specimens of the figures (126–1, 2, 5 in pl. 19) were N. nitidus actually, but those of the figures (126–3, 4, 6, 7–10) should belong to other species. Specimens of the figures (305– 5, 6 in pl. 50) in the book of Fujita were wrongly diagnosed, too. In order to identify this species well, its holotype (Figs 17–18) and intraspecific variations (Figs 13–16) are given in this study.

As mentioned above, this species also has the puzzle of “subspecies”. Fujita (2010) recorded six subspecies of N. nitidus without full discussions. Two of them, N. nitidus nitidus and N. nitidus hengshanensis , have been compared before. Relationships of other four ones, N. nitidus robustus Boileau, 1914 (from Laos); N. nitidus maekajanensis Ichikawa & Fujita, 1987 (from Northern Thailand), N. nitidus rutilans Bomans, 1989 (from Fujian, China) and N. nitidus hainanensis Mizunuma, 1994 (from Hainan, China) need to study in detail. We have briefly examined type specimens and type photos of them. In our opinion, three of them (robstus, hainanensis and rutilans) could be fully separate species, and maekajanensis could be a synonym of robustus. But it is difficult to clarify their taxonomic status unless a good number of specimens of these “subspecies” are examined. Because of this, we treated N. nitidus as a monotypic species temporarily in this paper.