Ceruchus yangi Huang, Imura & Chen, new species
Creators: name: Huang, Hao
name: Imura, Yûki
name: Chen, Chang-Chin
Publisher: name: Zenodo
Year: 2011
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Lucanidae
Ceruchus
Ceruchus yangi

description: 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.
description: Published as part of 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), pp. 1-42 in Zootaxa 2906 on pages 11-12, DOI: 10.5281/zenodo.277719