Nigidius wushuae Lin, 2022

Lin, J. - Z., 2022, A new species of the genus Nigidius MacLeay (Coleoptera: Lucanidae) from the Green Island, Eastern Taiwan, Far Eastern Entomologist 451, pp. 19-28 : 20-25

Nigidius wushuae Lin , sp. n.

http://zoobank.org/NomenclaturalActs/ 939E58E2-6B05-4C44-BECB-C9F1E5018561

Figs 1–5 , 13–15 , 24, 27 , 30, 31

TYPE MATERIAL. Holotype: ♂, Taiwan: Taitung County, Green Island , 180 m, 15.IX

2021, leg. J.-Z. Lin ( ASIZHX). Paratypes: 10♂, 2♀, same data as the holotype ( JZLT); Taitung

County , Green Island, VIII 2008, 9♂, 1♀, leg. T .- H. Hou ( JZLT) .

MATERIAL USED FOR COMPARISON. Nigidius lohi Kawahara,Toguchi et Ochi

2019: Taiwan: Pingtung County, Shouka , 500 m, 02.II 2018, 2♀, leg. Y.-F. Tsai ( JZLT) ;

Kaohsiung, Tengzhi , 1300 m, VIII 1992, 1♀, leg. K.-H.Yeh, det. W.-Y. Chou ( WICT) ;

Taitung County, Nanhui , 460 m, 19.VI 2019, 1♂, leg. S.-C. Yu ; Pingtung County, Mt.

Dahan, 1100 m, 12.VII 2017, 1♂, leg. J.-Z. Ling; Chiayi County, Alishan Township, 1220

m, 11. VI 2019, 1♂, leg. J.-Z. Ling; Hualien County Fuli Township , 800 m , 20. VII 2017, 1♀,

leg. J.-Z. Ling ( JZLT). Nigidius lewisi Boileau, 1905 : Japan: Okinawa Prefecture, Nago

City, 120 m, 21.VII 2020, 17♂, 3♀, leg. local collector ( JZLT). Nigidius sinicus Schenk ,

2011: China: Guangdong Province, Guangzhou City , 80 m, 16.VI 2021, 1♂, leg. local collector ( CZZHM) ; Hong Kong, 05.VII 2011, 2♂, 1♀, leg. local collector ( JZLT). Nigidius distinctus Parry, 1873 : China: Yunnan Province, Yingjiang County, Mangyun , 1200 m ,

26.VII 2019, 1♂, leg. local collector ( CZZHM) .

DESCRIPTION. Male (holotype). Length: 20.2 mm (including mandibles). Width: 6.6

mm. Body strongly convex dorsally, cylindrical and fairly elongate; dorsal and ventral surfaces strongly polished. Color piceous black; legs and antennae also black, though club segments of the somewhat reddish.

ventral view; 3 – abdominal segment IX, dorsal view; 4 – aedeagus, ventral view; 5 – the same, dorsal view.

pronotal punctation; 9 – labels. (Photo by Shuhei Nomura, NMNS).

Head punctate, punctures with long setae anteriorly; transversely quadrate in general appearance; clypeus bi-arcuate and distinctly separated by a transverse carina whose basal portion is fairly broadly quadrate, rather long, ca. 0.3 mm length. Eyes: canthus well developed, strongly concave at middle, with anterior corner slightly produced outward as an angular lobe and posterior one very strongly produced outward as a fairly sharply pointed projection, ca. 1.2 mm width. Mandibles shorter than head, simply formed at postero-basal portion, with an upright process which is simply formed and without an implicit inner tooth,

evenly and circularly incurved, and rounded distally; left mandible with two small obtuse teeth below and above at middle of inner margin, right one bearing a small obtuse tooth at the same place, with apex scarcely tumid at inner portion. Mentum slightly transverse, with anterior margin notched in widely opened at middle and forming arcuate lobe on each side,

densely, coarsely and shallowly punctate, the punctures partly becoming aspirate, partly chained and forming irregular transverse sculptures. Antennae with 10 segments, 3rd to 7th

one successively and very slightly broadened apically, club segments ordinary in size.

view; 10 – labels. (Photo by Christophe Rivier, MNHN).

Pronotum strongly convex dorsally, distinctly long and elongate, ca. 1.4 times as wide as long, wider than elytra; median longitudinal groove along midline not strong. Pronotal punctuation more uniformly punctate, rounded in middle and obliquely truncated behind,

with marginal border thick, anterior angles a little expanded laterally as rounded lobe;

posterior angles obliquely truncated; basal margin gently rounded in middle and very weakly sinuous on each side, with marginal border thick, scarcely serrate have a minute central process at posterior carina.

Scutellum tongue-shaped, rounded at apex, smooth marginally, very densely and strongly punctate medially.

Elytra somewhat reddish, ca. 1.4 times as long as wide, strongly convex dorsally, with hu-

meral tooth weak, but not sharply pointed; disc of each elytron with nine striae and 9 intervals;

striae broadly and rather shallowly grooved, 1st to 8th stria arranged with a longitudinal row of coarse punctures which are dense or partly chained, distinctly invading both margins of intervals and circular to semicircular in shape, 9th stria very broad, surface shiny.

lewisi ; 19–21 – N. lohi ; 22 – N. distinctus ; 23 – N. sinicus .

Legs. Protibia with 7 acute teeth decreasing in size proximally, slightly yellowish. Meso-

and metatibiae with 1 large external tooth below middle with 2–3 smaller accessory teeth proximally.

Male genitalia ( Figs 3–5 ) with transverse membranous area in the lateral of the basal part. Abdominal pleurite IX narrowly separated dorsally; abdominal sternite IX with apical expansion relatively slender; rounded at anterior margin; basal stalk not extended laterally;

genitalia with permanently everted internal sac (flagellum) long, about 1.7 times as long as parameters, with lateral margins more or less straight when manually extended. Median lobe relatively narrow, moderately widened in apical part; uncolored band transverse; caudal ventral plate of basal piece shorter and bifurcate not obvious.

wushuae sp. n.; 25, 28 – N. lewisi ; 26, 29 – N. lohi (holotype).

Female similar to male in general appearance but differs in the following characters: the corner lobe of the pronotum in males are more rounded and more developed than in females,

but this characteristic can be found in large individuals. If it is a small individual, it needs to be dissected to distinguish the gender.

Female genitalia. Each apex of hemisternite triangularly produced apically, with sharply hooked, rather long and well sclerotized stylus which is situated a little outside of triangular distal end ( Fig. 27 ).

DIAGNOSIS. The new species is similar to Nigidius lewisi from Japan, but can be distinguished from the latter by the following characteristics: 1) body somewhat larger, ca. 13.0–

20.6 mm, whereas in N. lewisi ca. 12.0–18.0 mm; 2) body distinctly longer and slenderer,

especially in elytra, whereas in N. lewisi it is relatively shorter and wider; 3) canthus well developed, with posterior margin very strongly produced outward as a fairly sharply pointed projection, whereas in N. lewisi it is less developed, with posterior margin more weakly produced;4) female genitalia with stylus distinctly longer and situated at triangular distal end,

while in N. lewisi genitalia with clearly slender and very sharp stylus. New species is also similar to N. lohi from Taiwan main island, but can be distinguished from the latter by the following characteristics: 1) pronotal punctuation surface more uniformly punctate, whereas in N. lohi surface variable with almost impunctate and coarsely punctate areas; 2) canthus with posterior margin very strongly produced outward as a fairly sharply pointed projection

(in N. lohi , canthus relatively shorter). Moreover, N. lohi in Taiwan live at an altitude of 500–

1300 meters, while N. wushuae sp. n. in Green Island lives below 200 meters above sea level.

DISTRIBUTION. The species is known only from the Green Island, East Taiwan.

ETYMOLOGY. The new species is named after the author’s grandmother Mrs. Lin Wu

Shu. She passed away during the author's research on this new species, take this to com-

memorate her.

31 – pronotal punctuation; 32 – N. lewisi , cantus; 33 – N. lohi , pronotal punctuation.

Figures

Figs 1–5. Nigidius wushuae sp. n. 1 – male holotype, habitus, dorsal view; 2 – the same,

Figs 13–23. Habitus of Nigidius spp., dorsal view. 13–15 – N. wushuae sp. n.; 16–18 – N.

Figs 24–29. Male (24–26) and female (27–29) genitalia of Nigidius spp. 24, 27 – N.

Figs 30–33. Head and pronotum of Nigidius spp. 30, 31 – N. wushuae sp. n.: 30 – cantus;