Lucanus langi Huang, He & Shi

Huang, Hao, He, Yang & Shi, Zheng, 2011, Description of two new species of Lucanus Scopoli (Coleoptera: Scarabaeoidea: Lucanidae) from southeastern Tibet, China, Zootaxa 2987, pp. 56-64 : 59-63

Lucanus langi Huang, He & Shi new species

Lucanus smithii Parry, 1862 , sensu Huang & Chen, 2010: 168, Figs. for male clypeolabrum, male habitus and male genitalia (misidentification).

Type material. Holotype ( Fig. 6 ): CHINA: Xizang (Tibet): 3, Linzhi Prefecture, Motuo County, 80 K, 1800m, VIII. 2005. Deposited in the entomological collection of Chongqing Museum, Natural History, Chongqing, China. Paratypes: CHINA: Xizang: 83, 1 Ƥ, Linzhi Prefecture, Motuo County, Hanmi Army Station, 1900–2000m, 26.VII.– 2.VIII. 2010, Yang He & Zheng Shi leg.; 1 paratype (3) in Natural History Museum, London; 2 paratypes (13, 1 Ƥ) in senior author’s collection (Qingdao, China); 2 paratypes (2 3) in Yang He’s collection (Hangzhou, China); 2 paratypes (2 3) in Zheng Shi’s collection (Hangzhou, China); 2 paratypes (2 3) in Peng-Yu Liu’s collection (Fuzhou, China).

Holotype description. Body length measured from apex of mandible to terminal tip of elytra: 48.5 mm.

Color and pubescence: Head blackish brown, sparsely clad with yellow pubescence on both dorsal and ventral surfaces. Mandible blackish brown, clad with yellow pubescence basally. Pronotum blackish brown, sparsely clad with yellow pubescence laterally. Elytra reddish brown, thinly clad with yellow pubescence along lateral margins. Ventral surface of thorax and abdomen blackish brown, clad with yellow pubescence; pubescence on metasternum markedly longer than on other areas. All femora and tarsi on both dorsal and ventral surfaces blackish brown. All tibiae on both surfaces reddish brown.

Head. Shape nearly rectangular; anterior ridge clearly defined and even in elevation; lateral and posterior ridges nearly straight, broadly rounded at posterolateral corners. Clypeolabrum clearly defined by transverse suture in front of frons, about 1.4 times as long as wide, glabrous; labrum and clypeus defined by lateral contraction medially; labrum plate-like, lacking dorsal branch, rounded and not bifurcate apically. Mandible about twice as long as head, evenly incurved, sharply pointed apically, with 1 small subapical ventral tooth; basal part swollen at inner margin, weakly serrate; major inner tooth associated with 1 small tooth in front and 1–2 small teeth behind. Antennal club with four antennomeres; antennomere 7 slender and sharply pointed apically; antennomeres 8–10 lamellate. Maxilla with long setose galea ( Fig. 19). Ligula bilobed, with branches rounded at apex ( Fig. 20), not pointed as in Lucanus cheni ( Fig. 21).

Legs. Protibia with 3–4 small teeth along lateral margin; apex bifurcate with branches blunt at tip. Mesotibia with 3 small lateral spines in addition to terminal spurs and spines. Metatibia with 2 lateral spines in addition to terminal spurs and spines.

Male genitalia. Last abdominal tergite with poorly-defined lateral angles. Last abdominal ventrite without apparent membranous area. Ventral plate of 9 th abdominal segment with basal part somewhat contracted before terminal expansion, with thin longitudinal membranous stripe along midline of terminal expansion. Aedeagus in dorsal view twice as long as wide. Basal piece in dorsal view triangular, nearly twice as long as parameres, with pair of sclerotized dorsal plates; ventral plate at caudal end of basal piece membranous. Paramere with slender basal process. Penis nearly as long as parameres, with flagellum about 5 times as long as parameres.

Male paratypes ( Figs. 7–8 , 11, 12). Body length measured from apex of mandible to terminal tip of elytra: 41– 57 mm.

Variation. Color variable: mandible, head, pronotum and elytra blackish brown to reddish brown; all tibiae on both surfaces entirely reddish brown to entirely blackish brown. Pubescence well marked in fresh specimens but absent in some old specimens. Mandible lacking a subapical tooth in some males. Basal part of mandible weakly to strongly serrate. Lateral spines of tibiae longer and sharper in most male specimens than in holotype. Large-sized males ( Fig. 6 ) with the apical fork of the mandible more opened, and with more secondary teeth. Ventral plate at the caudal end of the basal piece of male genitalia entirely membranous to partly sclerotized.

Female paratype ( Figs. 9 , 15, 16). Body length measured from apex of mandible to terminal tip of elytra: 36.5 mm.

Color and pubescence. All structures including femora and tibiae black on both dorsal and ventral surfaces. Head, pronotum and elytra glabrous, only antennal club with yellow pubescence. Ventral surface of the body with yellow pubescence dense on metasternum but sparse elsewhere.

Head. Canthus with both anterior and posterior angles clearly defined; anterior angle just inside of eye; lateral margin concave. Frontal and lateral ridges obsolete, not defined. Clypeolabrum in dorsal view transverse, flat at tip, not protruding forwards medially. Both mandibles with distinct dorsal tooth, 2 widely-separated inner teeth and large gap behind apex; lateral margin between 2 inner teeth concave and long.

Pronotum. Form about twice as wide as long, widest behind the middle; anterior angle rounded; lateral angles clearly defined but not pointed; posterior angle obtuse; lateral margin before the lateral angle evenly convex.

Female genitalia ( Figs. 32–35). Last abdominal tergite with poorly-defined lateral angles. Last abdominal ventrite with large semicircular membranous medially. Hemisternite broadly rounded apically, with outer apex not produced beyond inner apex; inner lateral margin of sclerotized part short. Spermatheca sclerotized and J-shaped. Spermathecal duct little more than twice as long as spermatheca. Spermathecal gland slightly longer than spermatheca. Central conjunction of the 9 th tergites protruding medially and narrow at tip.

Type locality. China, southeastern Tibet, Motuo.

Etymology. This species is dedicated to Dr. Song-Yun Lang (Chongqing, China), who kindly sent his lucanid collection to the senior author for study.

Diagnosis. This new species is similar to Lucanus smithii Parry, 1862 (Figs. 13, 17, 18), but can be distinguished by the following characters: male mandible with the inner margin of the basal part swollen and serrate (Figs. 12–13), female mandible with two inner teeth and a large gap behind the apex ( Figs. 16–18). Lucanus smithii should be placed into the L. fortunei group (sensu Huang & Chen 2010) because of the characters in the female mandible.

This new species is sympatric with Lucanus cheni at Motuo and is similar to the latter in some external characters. However the two species can be immediately distinguished from each other by the following characters: male mandible with the apical fork more widely opened in Lucanus cheni than in Lucanus langi (Figs. 10–11); male clypeolabrum bifurcate in Lucanus cheni but rounded in Lucanus langi (Figs. 10–11); ligula of male with the two branches pointed in Lucanus cheni but rounded in Lucanus langi ( Figs. 20–21); female canthus with the anterior angle outside of the eye in Lucanus cheni ( Fig. 2 ), but just inside of the eye in Lucanus langi ( Fig. 16). The genitalic difference between the two species is slight as in the cases of the other species of the L. lunifer group, but the following points are well marked: the sclerotized part of the penis with the lateral margins more concave in Lucanus cheni than in Lucanus langi ; the hemisternite of the female genitalia with the outer apex protruding beyond the inner apex in Lucanus cheni , but with the outer apex not beyond the inner apex in Lucanus langi .

This new species has some external characters in common with Lucanus imitator Boucher & Huang, 1991 but differs from the latter by the following characters: male clypeolabrum markedly longer and more rounded at apex; sclerotized part of the penis markedly narrower in front ( Figs. 27–30 ); hemisternite of the female genitalia with basal portion less sclerotized ( Figs. 34, 36); spermatheca of the female genitalia with the straight part markedly longer ( Figs. 34, 39 ); central conjunction of the 9 th tergites of female markedly narrower ( Figs. 35, 42).

This new species is also similar to the little known Lucanus singularis , but can be distinguished from the female holotype of the latter by the female clypeolabrum not protruding in the middle. The unique female holotype of Lucanus singularis has not been dissected so that the female genitalic characters remain unknown. However a series of specimens tentatively identified as Lucanus singularis are recently discovered from the Chayu area, southeastern Tibet, which match the most characters of the holotype of Lucanus singularis . A comparison between Lucanus langi and these specimens identified as Lucanus singularis shows more differences as follows: male clypeolabrum with apex rounded in Lucanus langi but pointed in Lucanus singularis ; major inner tooth of the male mandible with a few small teeth in Lucanus langi but without any other small teeth in Lucanus singularis ; male elytra darker in Lucanus singularis than in Lucanus langi ; basal belt of the flagellum of the penis slightly longer in Lucanus singularis ( Fig. 31 ) than in Lucanus langi ( Figs. 27–28 ); hemisternite of the female genitalia markedly longer in Lucanus singularis ( Fig. 37) than in Lucanus langi ( Fig. 34).

This new species can be distinguished from Lucanus dohertyi Boileau, 1911 , Lucanus sukkiti Fukinuki, 2004 and other species placed in the L. westermanni group (sensu Lacroix & Bomans 1973) by the basal part of the male mandible strongly swollen and serrate.

This new species should be placed in the L. lunifer group (sensu Huang & Chen 2010) with Lucanus cheni , Lucanus imitator and Lucanus singularis .

Figures

FIGURES 6 – 9. Lucanus langi habitus in dorsal view. 6 — male holotype; 7, 8 — male paratypes; 9 — female paratype. FIGURES 10 – 13. Male head in dorsal or anterodorsal view to show clypeolabrum and details of mandibles. 10 — Lucanus cheni holotype; 11 — Lucanus langi paratype; 12 — Lucanus langi paratype (same specimen as in Fig. 8); 13 — Lucanus smithii (Kurseong, India, photo by A. Galant). Abbreviations: s, basal part of mandible swollen and serrate on inner margin; b, clypeolabrum bifurcate at tip; nb, clypeolabrum non-bifurcate; ns, basal part of mandible non-serrate and not swollen. FIGURES 14 – 15. Lucanus langi, part of habitus in ventral view. 14 — male paratype (same specimen as in Fig. 7); 15 — female paratype (same specimen as in Fig. 9).

FIGURES 1 – 2. Lucanus cheni habitus in dorsal view. 1 — male holotype; 2 — female paratype.

FIGURES 27 – 31. Penis in ventral view. 27 — Lucanus langi (same specimen as in Fig. 8); 28 — Lucanus langi (same specimen as in Fig. 7); 29 — Lucanus imitator (Bomi, Tibet); 30 — Lucanus imitator (Dongjiu, Tibet); 31 — Lucanus singularis (Chayu, Tibet). Scale bars 1 mm for all. Abbreviations: b, end of basal belt of flagellum; w, width of one branch of the ventral sclerite in penis (showing difference between Lucanus langi and Lucanus imitator).

FIGURES 39 – 41. Spermatheca. 39 — Lucanus imitator (Bomi, Tibet); 40 — Lucanus singularis (Chayu, Tibet); 41 — Lucanus cheni (Motuo, Tibet). Abbreviations: l, length of the non-curved part as shown in length of the double arrow. FIGURES 42 – 44. Central conjunction of the 9 th tergites of female. 42 — Lucanus imitator (Bomi, Tibet); 43 — Lucanus singularis (Chayu, Tibet); 44 — Lucanus cheni (Motuo, Tibet).