Ceruchus yangi Huang, Imura & Chen

Huang, Hao, Imura, Yûki & Chen, Chang-Chin, 2011, Notes on the genus Ceruchus MacLeay from China, with the description of a new species (Coleoptera: Scarabaeoidea: Lucanidae), Zootaxa 2906, pp. 1-42 : 11-12

9. Ceruchus yangi Huang, Imura & Chen new species

( Figs. 13, 14 , 26 , 32–34 , 51 , 54–55, 64 , 132–161 , 213, 214 , 230 , 231 , 236, 237, 241, 242 , 262, 263 , 274–278 )

Type material. Holotype ( Figs. 13 , 33 , 132–139 , 237 ): CHINA: Guizhou Province: 3, Tongren City, Jiangkou County, Mount Fanjingshan, ca. 2000m, 25.VI.2009, X.-D. Yang leg. ( SHNU). Paratypes ( Figs. 236, 241, 242 , 262, 263 ): CHINA: Guizhou Province: 103 & 8ƤƤ, Tongren City, Jiangkou County, Mount Fanjingshan, 1888m & 2031m, 9.XI.2009, X.-D. Yang leg. (13, 1Ƥ in BMNH; 13, 1Ƥ in CHH; 83, 6ƤƤ in CCCC); 233 & 18ƤƤ, Kaili City, Leishan County, Mount Leigongshan, 1856m, 1954m & 1970m, 6-8.XI.2009, X.-D. Yang leg. (13, 1Ƥ in CHH; 223, 17ƤƤ in CCCC); 13, Kaili City, Leishan County, Mount Leigongshan, ca. 2000m, XI. 2009, Y. Imura leg. (Y. Imura). (63 & 4ƤƤ dissected).

Description of male holotype. Body length measured from apex of mandible to terminal tip of elytra: 18.2 mm. The color of body black on both dorsal and ventral surface. Maxilla and labium as in Ceruchus niger , without significant differences compared to those of other species. All characters as stated in table 1.

Description of male paratypes. Body length measured from apex of mandible to terminal tip of elytra: 14.7– 20.8 mm. All the paratypes share the characters stated in table 1. The individual variations appear in the following characters: size of body, length and detailed shape of the dorsal tooth on the mandible, size and detailed shape of the mentum, appearance or absence of the central depression on the mentum. The male genital characters are very constant among the six specimens from two different localities dissected.

Description of female paratypes. Body length measured from apex of mandible to terminal tip of elytra: 14.5–16.4 mm. All the female specimens examined share all the characters stated in table 2. The individual variations appear in some female genital characters as follows: specimens from Leigongshan have stylus markedly longer and spermathecal gland markedly shorter than in specimens from Fanjingshan.

Diagnosis and discussion. This new species is most similar to Ceruchus reginae in morphological distance, only differing in six male characters ( Table 1). However, this similarity is largely due to our poor knowledge of Ceruchus reginae , of which only a few characters have been properly investigated. Similarly, Ceruchus deuvei , Ceruchus katerinae and Ceruchus niger also possess very few different male characters from Ceruchus reginae . Nevertheless, Ceruchus yangi can be easily distinguished from Ceruchus reginae by the entire absence of the yellow brush of setae on the mesotibia and the peculiar shape of the penis that is noticeably swollen in middle.

Ceruchus yangi can be distinguished from Ceruchus chuduraziensis by the following characters: 1) male mentum markedly more transverse; 2) ventral distal corner of the paramere not sharply produced; 3) penis in ventral view wide at terminal end, not narrower than base; 4) dorsal surface of the penis in lateral view not strongly incurved at basal part; 5) female mentum markedly more transverse; 6) anterior angle of the female pronotum not sharply pointed. There are likely more differences between these species, as some important characters have not been properly investigated for Ceruchus chuduraziensis .

Ceruchus yangi is also similar to Ceruchus niger , differing in only nine characters for both sexes. These species are considered separate because they differ from each other by one male genital character ( Table 1) and four female genital characters ( Table 2). In external features, Ceruchus yangi can be easily distinguished from Ceruchus niger by the dorsal tooth of mandible directed more forwards, the absence of ventral tooth on mandible, the flat anterior margin of the mentum, and the absence of the yellow brush of setae on the mesotibia. However, the females of these species cannot be reliably distinguished using external features and an examination of female genitalia is required.

Ceruchus yangi can be easily distinguished from Ceruchus luojishanensis by the following characters: 1) pronotum less transverse in both sexes; 2) lateral margins of the pronotum less convex in both sexes; 3) elytra of both sexes relatively longer in proportion to width of the body; 4) longitudinal depressions on elytra of both sexes deeper; 5) central split on caudal margin of the basal piece of the aedeagus more apparent, with two sides protruding posteriorly, forming an m-shaped caudal margin; 6) caudal end of penis in ventral view wider, with posterolateral shoulders well marked; 7) mola of the female mandible with double central teeth on inner margin; 8) sclerotized part of the hemisternite in female genitalia with inner lateral margin shorter than distal margin of hemisternite; 9) stylus of female genitalia with outer terminal corners more protruding.

Ceruchus tabanai might be a subspecies of Ceruchus sinensis , but is different from Ceruchus yangi . The differences between these taxa can be found in Tables 1-2.

Etymology. This new species is named after the collector of the type material, Mr. Xiao-Dong Yang.

Distribution ( Fig. 293 ). Only known from two localities in Guizhou Province: Mount Leigongshan and Mount Fanjingshan.

Figures

FIGURE 230. Female genitalia of Ceruchus yangi, Fanjingshan (specimen not figured elsewhere) consisting of sclerotized part in both ventral and dorsal views at top, the last abdominal tergite and ventrite, and the whole female genitalia at bottom. Scale bar 1 mm for all. Abbreviations: ag accessory gland; sd spermathecal duct; bc bursa copulatrix; s spermatheca; es entrance of spermatheca; sg spermathecal gland.

FIGURE 231. Female genitalia of Ceruchus yangi, Leigongshan (same specimen as Fig. 262) consisting of sclerotized part in both ventral and dorsal views at top, the last abdominal tergite and ventrite, and the whole female genitalia at bottom. Scale bar 1 mm for all. Abbreviations: mo median oviduct; ag accessory gland; sd spermathecal duct; s spermatheca; es entrance of spermatheca; sg = spermathecal gland.

FIGURE 293. Distribution of Ceruchus species in China

FIGURES 10 – 24. Mandible and head of male in lateral view. 10 — Ceruchus lignarius lignarius (same specimen as Fig. 233); 11 — Ceruchus lignarius monticola (same specimen as Fig. 234); 12 — Ceruchus lignarius nodai (same specimen as Fig. 235); 13 — Ceruchus yangi (same specimen as Fig. 237, holotype); 14 — Ceruchus yangi (same specimen as Fig. 236, paratype); 15 — Ceruchus tabanai (holotype); 16 — Ceruchus sinensis (same specimen as Fig. 239); 17 — Ceruchus niger (same specimen as Fig. 240); 18 — Ceruchus niger (same specimen as Fig. 245); 19 — Ceruchus luojishanensis (holotype); 20 — Ceruchus minor (same specimen as Fig. 249); 21 — Ceruchus minor (specimen not figured elsewhere); 22 — Ceruchus minor (same specimen as Fig. 252); 23 — Ceruchus minor (same specimen as Fig. 250); 24 — Ceruchus katerinae (same specimen as Fig. 253). Scale bar 4 mm for all. Abbreviations: d = dorsal tooth; v = ventral tooth.

FIGURES 25 – 28. Antenna of male. 25 — Ceruchus minor; 26 — Ceruchus yangi; 27 — Ceruchus niger; 28 — Ceruchus katerinae.

FIGURES 29 – 45. Mentum of male in ventral view. 29 — Ceruchus lignarius lignarius (same specimen as Fig. 233); 30 — C. luojishanensis (holotype); 31 — C. tabanai (holotype); 32 — C. yangi, Leigongshan (same specimen as Fig. 236, paratype); 33 — C. yangi, Fanjingshan (same specimen as Fig. 237, holotype); 34 — C. yangi, Leigongshan (same specimen as Fig. 242, paratype); 35 — C. sinensis (same specimen as Fig. 238); 36 — C. sinensis (same specimen as Fig. 234); 37 — C. niger, Laojunshan (same specimen as Fig. 240); 38 — C. niger, Yulongxueshan (same specimen as Fig. 245); 39 — C. niger, Laojunshan (same specimen as Fig. 243); 40 — C. minor, Qinling (same specimen as Fig. 249); 41 — C. minor, Dabashan (corresponding to Fig. 250); 42 — C. minor, Diebu of Gansu (specimen not figured elsewhere); 43 — C. minor, Diebu of Gansu (same specimen as Fig. 252); 44 — C. minor, Zhouqu of Gansu (same specimen as Fig. 256); 45 — C. katerinae (same specimen as Fig. 253). Scale bar 3 mm for all.

FIGURES 46 – 53. Mesofemur and mesotibia in ventral view. 46 — Ceruchus katerinae; 47 — Ceruchus lignarius monticola; 48 — Ceruchus minor; 49 — Ceruchus niger; 50 — Ceruchus sinensis; 51 — Ceruchus yangi; 52 — Ceruchus luojishanensis; 53 — Ceruchus tabanai.

FIGURES 54 – 67. Last abdominal tergite and ventrite of males. 54 — Ceruchus yangi, both from Leigongshan; 55 — Ceruchus yangi, both from Fanjingshan; 56 — Ceruchus minor, Qinling; 57 — Ceruchus minor, Dabashan; 58 — Ceruchus minor, Zhouqu of Gansu; 59 — Ceruchus minor, Diebu of Gansu; 60 — Ceruchus niger, Weixi; 61 — Ceruchus sinensis, Baoshan; 62 — Ceruchus sinensis, Baoshan; 63 — Ceruchus lignarius monticola, Japan; 64 — Ceruchus yangi, Leigongshan; 65 — Ceruchus niger, Weixi; 66 — Ceruchus minor, Diebu of Gansu; 67 — Ceruchus sinensis, Baoshan. Scale bar 1 mm for all.

FIGURES 132 – 139. Male genitalia of Ceruchus yangi, Holotype, Fanjingshan (same specimen as Fig. 237). 132 — Ninth abdominal segment in ventral view; 133 — Ninth abdominal segment in dorsal view; 134 — whole genitalia in ventral view; 135 — whole genitalia in dorsal view; 136 — whole genitalia in lateral view; 137 — penis detached in lateral view; 138 — penis detached in lateral view; 139 — penis detached in dorsal view. Scale bar 1 mm for all. Abbreviations: c = central split on caudal margin of basal piece of aedeagus; i = inner sclerite near the dorsal margin of the paramere; e = endophallus.

FIGURES 140 – 145. Male genitalia of Ceruchus yangi, paratype, Fanjingshan (specimen not figured elsewhere). 140 — Ninth abdominal segment in ventral view; 141 — Ninth abdominal segment in dorsal view; 142 — whole genitalia in ventral view; 143 — whole genitalia in dorsal view; 144 — whole genitalia in lateral view; 145 — whole genitalia in dorsolateral view. Scale bar 1 mm for all. Abbreviation: i = inner sclerite near the dorsal margin of the paramere.

FIGURES 146 – 153. Male genitalia of Ceruchus yangi, paratype, Leigongshan (same specimen as Fig. 236). 146 — Ninth abdominal segment in ventral view; 147 — Ninth abdominal segment in dorsal view; 148 — whole genitalia in ventral view; 149 — whole genitalia in dorsal view; 150 — whole genitalia in lateral view; 151 — penis detached in lateral view; 152 — penis detached in lateral view; 153 — penis detached in dorsal view. Scale bar 1 mm for all. Abbreviations: c = central split on caudal margin of basal piece of aedeagus; i = inner sclerite near the dorsal margin of the paramere.

FIGURES 154 – 161. Male genitalia of Ceruchus yangi, paratypes, Leigongshan (same specimen as Figs. 241 – 242). 154 — whole genitalia in ventral view; 155 — whole genitalia in lateral view; 156 — whole genitalia in ventral view; 157 — whole genitalia in lateral view; 158 — penis detached in lateral view; 159 — penis detached in dorsal view; 160 — penis detached in lateral view; 161 — penis detached in dorsal view. Scale bar 1 mm for all. Abbreviation: e = endophallus.

FIGURES 210 – 224. Detached structures of females, consisting of mandibles in dorsal view, mentum in ventral view, pronotum in dorsal view, protibia in dorsal view, and mesofemur in ventral view. 210 — Ceruchus lignarius lignarius (same specimen as Fig. 259); 211 — C. luojishanensis (paratype); 212 — C. tabanai (paratype); 213 — C. yangi (same specimen as Fig. 262); 214 — C. yangi (same specimen as Fig. 263); 215 — C. niger (same specimen as Fig. 264); 216 — C. niger (same specimen as Fig. 265); 217 — C. niger (same specimen as Fig. 266); 218 — C. niger (same specimen as Fig. 267); 219 — C. deuvei (same specimen as Fig. 268); 220 — C. minor (same specimen as Fig. 269); 221 — C. minor (same specimen as Fig. 270); 222 — C. minor (specimen not figured elsewhere); 223 — C. sinensis (same specimen as Fig. 272); 224 — C. katerinae (same specimen as Fig. 273). Abbreviations: md = mandibles; me = mentum; p = pronotum; pt = protibia; mf = mesofemur; l = lateral protuberance; n = no central tooth on mola; d = double central teeth on mola; s = single central tooth on mola; t = transversal carina; f = flattened marginal area of the pronotum.

FIGURES 233 – 248. Habitus of male Ceruchus in dorsal view. 233 — Ceruchus lignarius lignarius (Hokkaido, Japan); 234 — Ceruchus sinensis (Yaojiaping, Lushui, W. Yunnan); 235 — Ceruchus tabanai (holotype); 236 — Ceruchus yangi, paratype (Leigongshan, Guizhou); 237 — Ceruchus yangi, holotype (Fanjingshan, Guizhou); 238 — Ceruchus sinensis (Baoshan, Yunnan); 239 — Ceruchus sinensis (Baoshan, Yunnan); 240 — Ceruchus niger (Laojunshan, Yunnan); 241 — Ceruchus yangi, paratype (Leigongshan); 242 — Ceruchus yangi, paratype (Leigongshan); 243 — Ceruchus niger (Laojunshan, Yunnan); 244 — Ceruchus niger (Laojunshan, Yunnan); 245 — Ceruchus niger (Yulongxueshan, Yunnan); 246 — Ceruchus niger (Yulongxueshan, Yunnan); 247 — Ceruchus niger (Weixi, Yunnan); 248 — Ceruchus niger (Muli, Sichuan). Scale bar 5 mm for all.

FIGURES 259 – 273. Habitus of female Ceruchus in dorsal view. 259 — Ceruchus lignarius lignarius (Hokkaido, Japan); 260 — Ceruchus luojishanensis (paratype); 261 — Ceruchus tabanai (paratype); 262 — Ceruchus yangi, paratype (Leigongshan, Guizhou); 263 — Ceruchus yangi, paratype (Leigongshan, Guizhou); 264 — Ceruchus niger (Laojunshan, Yunnan); 265 — Ceruchus niger (Yulongxueshan, Yunnan); 266 — Ceruchus niger (Weixi, Yunnan); 267 — Ceruchus niger (Muli, Sichuan); 268 — Ceruchus deuvei (Lixian, Sichuan); 269 — Ceruchus minor (Dabashan, Chongqing); 270 — Ceruchus minor (Diebu, Gansu); 271 — Ceruchus minor (Micangshan, Sichuan); 272 — Ceruchus sinensis (Yaojiaping, Lushui, Yunnan); 273 — Ceruchus katerinae (Hailuogou, Sichuan). Scale bar 5 mm for all.

FIGURES 274 – 292. Field observations of Chinese Ceruchus. 274 — habitat of Ceruchus yangi (Mount Leigongshan, 1856 m, 6 September 2009, by X. - D. Yang); 275 — a standing dead tree inhabited by Ceruchus yangi (by X. - D. Yang); 276 – 277 — newly emerged male adult of Ceruchus yangi in pupal cell; 278 — female adult of Ceruchus yangi found in white wood; 279 – 280 — habitat of Ceruchus katerinae (Hailuogou, Sichuan, 3100 m, 30 July 2006, by L. Tang); 281 – 283 — male of Ceruchus katerinae crawling on living stem of Abies tree (by L. Tang); 284 — habitat of Ceruchus niger (Mount Laojunshan, 3500 m, 13 June 2009, by J. - Q. Zhu); 285 – 286 — fallen dead coniferous tree inhabited by Ceruchus niger (by J. - Q. Zhu); 287 — male adult of Ceruchus niger found in the powdery wood (by J. - Q. Zhu); 288 — habitat of Ceruchus minor (Zhouqu, 2340 m, 18 October 2009, by X. - D. Yang); 289 – 290 — a living broadleaf inhabited by Ceruchus minor (by X. - D. Yang); 291 — adult of Ceruchus minor found in white wood of the tree (by X. - D. Yang); 292 — newly emerged male adult of Ceruchus minor in white wood taken from the habitat at Diebu (by H. Huang).