Dorcus tianlongi Wang & Zhou, 2019

Wang, Cheng-Bin & Zhou, Chao, 2019, Dorcus tianlongi, a new species from central China (Coleoptera: Lucanidae: Lucaninae), Zootaxa 4691 (5), pp. 575-588 : 576-581

Dorcus tianlongi Wang & Zhou , new species [KAEƛẃ]

( Figs. 1 A–C; 3A–C; 4A–B; 5A–B; 6A–B; 7A–C; 9A–C; 10A–C; 11A–B; 12A, C, E)

Type material. Holotype: ♂, CHINA, Guizhou: Tongren City, Jiangkou County, Fanjingshan [= Mt. Fanjing, ẄṎ Ɯ], Wanbaoyan , 2000 m, 27.VII.2017, Tian-Long He leg. ( MYNU) . Paratypes: 2♂♂ 5♀♀, same data as holotype (1♂ 1♀ in CMZA, 1♂ 4♀♀ in CTLH) ; 5♂♂ 2♀♀, same data as holotype except: 16.VII.2017 (1♀ in CCZC, 1♂ 1♀ in CLHC and 4♂♂ in CTLH) ; 2♂♂ 1♀, same data as holotype except: 20.VIII.2018 ( CCZC) ; 2♂♂, same data as holotype except: 1775 m, 19–22. VI.2016, Bo-Yan Li ( CBYL) ; 4♂♂ 2♀♀, CHINA, Guizhou: Qiandongnan Prefec- ture, Leishan County, Leigongshan [= Mt. Leigong, Ñ ẌƜ], Lianhuaping , 1600 m, 11. VI.2017, Tian-Long He leg. ( CTLH) ; 2♂♂ 5♀♀, same data as previous except: 13. VI.2017 (2♂♂ 2♀♀ in CCZC and 3♀♀ in CTLH) .

Description of holotype, male. Size moderate for the genus, body 41.6 mm long. Length of different body parts: head (6.3 mm), mandible (9.9 mm), pronotum (7.6 mm), elytra (17.5 mm); width: head (14.5 mm), pronotum (15.9 mm), elytra (13.2 mm).

Habitus ( Figs. 1 A–C). Color black. Body generally glabrous; some distinct, recumbent, yellowish and sparse pubescence present on lateral parts of metasternum.

Head ( Fig. 4A ) wider than long, widest at eyes. Clypeolabrum shortly transverse, widely and shallowly emarginate at apical margin. Mandible about 1.6 times as long as head, distinctly incurved at middle; one single inner tooth ( Fig. 4B ) present at middle, pointing forward and truncated at apex. Postocular margin bulged into a process. Antennal club with 3 antennomeres; antennomere VII sharp at inner apical angle; antennomeres VIII–X lamellate.

Pronotum ( Fig. 4A ) 2.1 times wider than long, widest just after the obtuse lateral angles.

Legs ( Figs. 1 A–B). Protibia with 7–8 large teeth, more or less bluntly rounded along outer margin; apex bifurcate with branches bluntly rounded at tip. Except apical spurs and spines, each mesotibia and metatibia with one lateral spine, distinctly sharper than the one on protibia.

Male genitalia. Abdominal tergite VIII ( Fig. 6A ) with a subtriangular membranous area at middle of basal part; abdominal sternite VIII ( Fig. 6B ) with a transverse membranous area at middle of basal part. Abdominal tergite IX ( Fig. 7C ) with lateral extensions relatively slender; abdominal pleurite IX ( Fig. 7B ) conterminous dorsally; abdominal sternite IX ( Fig. 7A ) with a small membranous area at middle of apical margin. Aedeagus ( Fig. 9A ) in ventral view about 2.8 times longer than wide. Basal piece ( Figs. 9 A–B) distinctly constricted in basal part, about 1.7 times as long as parameres, with a pair of sclerotized dorsal plates ( Fig. 9B ); ventral plate ( Fig. 9A ) not bifurcate at apex at distal end of basal piece. Paramere without basal process ( Fig. 9B ); apex weakly upturned ( Fig. 9C ). Penis ( Figs. 9A ; 10A ) relatively slender and biarcuate, distinctly shorter than parameres. Flagellum ( Figs. 9 A–C) long, trifurcate, about 5.5 times as long as parameres, apex strongly enlarged.

Male paratypes. Body 40.2–43.5 mm long. All male types have the same body shape, without evident variations.

Female paratypes. Body 24.0– 24.8 mm long. Length of different body parts (n=6): head (3.4 mm), mandible (2.0 mm), pronotum (5.6 mm), elytra (13.1 mm); width: head (6.7 mm), pronotum (9.0 mm), elytra (8.9 mm).

Habitus ( Figs. 3 A–C). Color black. Body generally glabrous; some fine, recumbent, yellowish and sparse pubescence present on lateral parts of metasternum. Longitudinal carinae on elytra relatively narrow.

Head ( Fig. 5A ). Canthus with rounded posterior angle. Clypeolabrum small, distinctly emarginate in middle. Right and left mandibles similar to each other, without dorsal tooth, with one inner tooth and one slight protuberance basally. Postocular margin relatively long.

Pronotum ( Fig. 5A ) 1.6 times wider than long, widest at about apical 4/9 of its length. Lateral margin crenulated. Disc coarsely punctate except smooth areas on both sides of the midline.

Legs ( Figs. 3 A–B). Protibia without teeth, weakly undulated along outer margin; apex obliquely substraight. Except apical spurs and spines, each mesotibia and metatibia with one lateral spine.

Female genitalia. Abdominal tergite VIII ( Fig. 11A ) simple, without obvious membranous area and lateral angle. Abdominal sternite VIII ( Fig. 11B ) with a T-shaped membranous area along the midline and weekly emarginate at middle of posterior margin. Hemisternite ( Figs. 12A, C ) with apical part short, stout and straight at apical margin. Central conjunction of tergite IX ( Fig. 12A ) protruding medially and roundly narrowed at tip. Spermatheca ( Fig. 12C ) inflated, reniform and weakly sclerotized; pear-like in apical view ( Fig. 12E ). Spermathecal duct ( Fig. 12C ) short. Spermathecal gland ( Fig. 12C ) small, globular and membranous. Spermathecal gland duct ( Fig. 12C ) slender and thin. Accessory gland ( Fig. 12C ) clavate.

Etymology. The new species is dedicated to its collector, Mr. Tian-Long He (Huainan, Anhui, China), an enthusiastic amateur entomologist. The name is a noun in the genitive case.

Distribution. China (Guizhou).

Differential diagnosis. This new species should be assigned to the Dorcus reichei group (sensu Huang & Chen 2013). It resembles D. liyingbingi in general appearance, but can be distinguished by the combination of the following characters: in D. tianlongi new species, male: head widest at eyes ( Fig. 4A ), inner tooth of mandible present at middle, pointing forward and truncated at apex ( Figs. 4 A–B), lateral angles of pronotum obtuse ( Fig. 4A ), outer teeth of protibia more or less bluntly rounded ( Figs. 1 A–B), abdominal sternite VIII with a transverse membranous area at middle of basal part ( Fig. 6B ), abdominal pleurite IX conterminous dorsally ( Fig. 7B ), abdominal sternite IX with a small membranous area at middle of apical margin ( Fig. 7A ), ventral plate at apical end of aedeagal basal piece not bifurcate at apex ( Fig. 9A ), penis relatively slender ( Figs. 9A ; 10A ); female: hemisternite with apical part shorter ( Fig. 12C ); spermatheca reniform ( Fig. 12C ). While in D. liyingbingi , male: head widest at postocular process ( Fig. 4C ), inner tooth of mandible present at basal 1/3, pointing inward and rounded at apex ( Figs. 4 C–D), lateral angles of pronotum acute ( Fig. 4C ), outer teeth of protibia more or less acute ( Figs. 1 D–E), abdominal sternite VIII with a pair of membranous areas at middle of basal part ( Fig. 6D ), abdominal pleurite IX separated dorsally ( Fig. 7E ), abdominal sternite IX with a small protuberance at middle of apical margin ( Fig. 7D ), ventral plate at apical end of aedeagal basal piece bifurcate at apex ( Fig. 9A ), penis relatively wide ( Figs. 9D ; 10D ); female (Huang & Chen 2013: 465, fig. 122-5): hemisternite with apical part longer; spermatheca globular.

Dorcus tianlongi new species is also somewhat similar to D. mencius , but it is not difficult to separate the two taxa by the combination of the following characters: in D. tianlongi new species, male: mandible incurved at middle ( Fig. 4A ), single-toothed ( Figs. 4 A–B), inner tooth present at middle and truncated at apex ( Figs. 4 A–B), outer teeth of protibia more or less bluntly rounded ( Figs. 1 A–B), abdominal tergite VIII with membranous area relatively smaller ( Fig. 6A ), abdominal sternite VIII with a transverse membranous area at middle of basal part ( Fig. 6B ), abdominal tergite IX with lateral extensions relatively slender ( Fig. 7C ), abdominal pleurite IX conterminous dorsally ( Fig. 7B ), abdominal sternite IX with a small membranous area at middle of apical margin ( Fig. 7A ), penis relatively slender and distinctly curved inward in middle ( Figs. 9A ; 10A ); female: canthus with rounded posterior angle ( Fig. 5A ), left mandible with one inner tooth and one slight protuberance basally ( Fig. 5A ), inner tooth ahead of middle ( Fig. 5A ), pronotal disc coarsely punctate except smooth areas on both sides of the midline ( Fig. 5A ), protibia without teeth, weakly undulated along outer margin ( Figs. 3 A–B), T-shaped membranous area of abdominal sternite VIII with basal part oblong ( Fig. 11B ), hemisternite with apical part shorter and straight at apical margin ( Figs. 12A, C ), spermatheca smaller, pear-like in apical view ( Figs. 12C, E ), spermathecal gland duct slender and thin ( Fig. 12C ), accessory gland clavate ( Fig. 12C ). While in D. mencius , male: mandible incurved at apical 1/3 ( Figs. 4E, G ), triple-toothed in large size ( Figs. 4 E–F) or double-toothed (the small one vestigial but still visible) in small size ( Figs. 4 G–H), the largest inner tooth present at basal 1/3 and rounded at apex ( Figs. 4 E–H), outer teeth of protibia more or less acute ( Figs. 2 A–B, D–E), abdominal tergite VIII with membranous area relatively broader ( Figs. 6E, G ), abdominal sternite VIII with a pair of ( Fig. 6F ) or a transverse ( Fig. 6H ) membranous area at middle of basal part, abdominal tergite IX with lateral extensions relatively stouter ( Figs. 8C, F ), abdominal pleurite IX separated dorsally ( Figs. 8B, E ), abdominal sternite IX with a transverse membranous area along apical margin ( Figs. 8A, D ), penis relatively wide and hardly curved in middle ( Figs. 9G ; 10G, J ); female: canthus without posterior angle ( Fig. 5C ), left mandible with one inner tooth and three small tubercles basally ( Fig. 5C ), inner tooth around middle ( Fig. 5C ), pronotal disc smooth, only coarsely punctate along margins ( Fig. 5C ), protibia with 6–7 teeth ( Figs. 3 D–E), Tshaped membranous area of abdominal sternite VIII with basal part transverse ( Fig. 11D ), hemisternite with apical part longer and round at apical margin ( Figs. 12B, D ), spermatheca larger, more elongated in apical view ( Figs. 12D, F ), spermathecal gland duct short and thick ( Fig. 12D ), accessory gland oblong ( Fig. 12D ).

Figures

FIGURES 1A–F. Male habitus of Dorcus species in dorsal (A, D), ventral (B, E) and lateral (C, F) view. A–C, D. tianlongi Wang & Zhou, new species, holotype; D–F, D. liyingbingi Huang & Chen, 2013 from Yunnan. Scale bar = 1.0 cm.

FIGURES 2A–F. Male habitus of Dorcus mencius (Kriesche, 1935) in dorsal (A, D), ventral (B, E) and lateral (C, F) view. A–C, large size from Henan; D–F, small size from from Sichuan. Scale bar = 1.0 cm.

FIGURES 3A–F. Female habitus of Dorcus species in dorsal (A, D), ventral (B, E) and lateral (C, F) view. A–C, D. tianlongi Wang & Zhou, new species, paratype; D–F, D. mencius (Kriesche, 1935) from Henan. Scale bar = 1.0 cm.

FIGURES 4A–H. Male heads and pronota (A, C, E, G) of Dorcus species in dorsal view and corresponding mandibles (B, D, F, H) in lateral view. A–B, D. tianlongi Wang & Zhou, new species, holotype; C–D, D. liyingbingi Huang & Chen, 2013 from Yunnan; E–F, D. mencius (Kriesche, 1935), large size from Henan; G–H, D. mencius (Kriesche, 1935), small size from Sichuan. Scale bar = 1.0 cm.

FIGURES 5A–D. Female heads and pronota (A, C) of Dorcus species in dorsal view and corresponding mandibles (B, D) in lateral view. A–B, D. tianlongi Wang & Zhou, new species, paratype; C–D, D. mencius (Kriesche, 1935) from Henan. Scale bar = 1.0 cm.

FIGURES 6A–H. Male abdominal tergites VIII (A, C, E, H) and sternites VIII (B, D, F, H) of Dorcus species. A–B, D. tianlongi Wang & Zhou, new species, holotype; C–D, D. liyingbingi Huang & Chen, 2013 from Yunnan; E–F, D. mencius (Kriesche, 1935), large size from Henan; G–H, D. mencius (Kriesche, 1935), small size from Sichuan. Scale bar = 1.0 mm.

FIGURES 7A–F. Male abdominal segments IX of Dorcus species in ventral (A, D), dorsal (B, E) and lateral (C, F) view. A–C, D. tianlongi Wang & Zhou, new species, holotype; D–F, D. liyingbingi Huang & Chen, 2013 from Yunnan. Scale bar = 1.0 mm.

FIGURES 8A–F. Male abdominal segments IX of Dorcus mencius (Kriesche, 1935) in ventral (A, D), dorsal (B, E) and lateral (C, F) view. A–C, large size from Henan; D–F, small size from from Sichuan. Scale bar = 1.0 mm.

FIGURES 9A–I. Aedeagi of Dorcus species in ventral (A, D, G), dorsal (B, E, H) and lateral (C, F, I) view. A–C, D. tianlongi Wang & Zhou, new species, holotype; D–F, D. liyingbingi Huang & Chen, 2013 from Yunnan; G–I, D. mencius (Kriesche, 1935), large size from Henan. Scale bar = 1.0 mm.

FIGURES 10A–L. Penes of Dorcus species in ventral (A, D, G, J), dorsal (B, E, H, K) and lateral (C, F, I, L) view. A–C, D. tianlongi Wang & Zhou, new species, holotype; D–F, D. liyingbingi Huang & Chen, 2013 from Yunnan; G–I, D. mencius (Kriesche, 1935), large size from Henan; J–L, D. mencius (Kriesche, 1935), small size from Sichuan. Scale bar = 1.0 mm.

FIGURES 11A–D. Female abdominal tergites VIII (A, C) and sternites VIII (B, D) of Dorcus species. A–B, D. tianlongi Wang & Zhou, new species, paratype; C–D, D. mencius (Kriesche, 1935) from Henan. Scale bar = 1.0 mm.

FIGURES 12A–F. Female genitalia of Dorcus species: integrals (C–D), apical parts of hemisternites (A–B) in ventral view and spermathecae (E–F) in apical view. A, C, E, D. tianlongi Wang & Zhou, new species, paratype; B, D, F, D. mencius (Kriesche, 1935) from Henan. Scale bars = 1.0 mm.