Prismognathus davidis Deyrolle 1878
Creators: name: Huang, Hao
name: Chen, Chang-Chin
Publisher: name: Zenodo
Year: 2012
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Lucanidae
Prismognathus
Prismognathus davidis

description: Prismognathus davidis Deyrolle, 1878
(Figs. 22–23, 31, 35–46, 79 –86, 92, 108–110, 117–119, 138–142, 168–172, 200–203, 220, 234)
Prismognathus davidis Deyrolle in Deyrolle & Fairmaire 1878: 94 [type locality: central China]; Didier & Séguy, 1952: partim [plate 91, Figs. 3–7]; Mizunuma & Nagai, 1994: 238, plate 138, Fig. 236-1; Krajcik 2008: 141, explanation for type locality [syntype labeled from Pekin = Beijing]; Fujita 2010: 164, plate 99, Figs. 490-1-3.
Prismognathus davidis cheni Bomans & Ratti, 1973: 282 –284 [type locality: Li-Shan, Taiwan], Fig. 1, male; Mizunuma & Nagai, 1994: 238, plate 51, Figs. 236-2–4. Valid subspecies.
Prismognathus davidis nigerrimus Sakaino & Yu, 1993: 14 [type locality: Pilu, Hualien, Taiwan], Figs. 1–3. New synonym of P. davidis cheni.
Prismognathus klapperichi: Wan et al. 2007: 54, partim [1 male and 2 females from Mt. Tianmushan], 55, Fig. 12. Misidentification.
Prismognathus cheni: Fujita 2010: 164, plate 99, Figs. 489-1–2. Incorrect status of P. davidis cheni.
Material examined. CHINA: Beijing: 1 3 (MNHN, Fig. 43), syntype, labeled as “ TYPE / Pekin/ Ex-Musaeo ARM. DAVID 0061/ Prismognath davidis H.D. Pekin/ Prismognathus davidis Deyr. J.P. Lacroix det. 1972”; 8 3
(CHH), 7 ƤƤ (CHH), Xiaolongmen, 1100-1300m, VII-VIII. 2000-2004; 3 3 (CHH), 2 ƤƤ (CHH), Yunmengshan, VIII.1998; 3 3 (CHH), 2 ƤƤ (CHH), Puwa, VII.2005. Hebei Province: 2 3 (CHH), Qinhuangdao, Zushan, VIII.2003. Shaanxi Province: 4 3, 3 ƤƤ, Zhouzhi County, Houzhenzi, 1300m, VII.2007; 2 3 (CHH), 2 ƤƤ (CHH), Foping County, Qinling-Daoban, 2800m, V.2008, larvae collected by H. Huang, reared in laboratory and emerged in III.2008; 1 3, 3 ƤƤ (IEAS), Taibaishan, Haopingshi, 2700m, VI-IX.2009. Gansu Province: 1 3, 2 ƤƤ, Zhouqu County, Shatanlinchang, VII.2004, W.-I. Chou leg. Chongqing: 2 3, Chengkou County, Huang-an, 1795m, V.2009, larvae collected by X.-D. Yang, emerged in III. 2010. Henan Province: 1 Ƥ (SNUC), Funiu Mts., 1500m, VIII.2004, J.-Y. Hu & L. Tang leg.; 2 3 (IEAS), Songxian County, Baiyunshan, 1300m, 15.VIII.2000, Shen, Ren & Liu leg. Hubei Province: 1 3, 1 Ƥ (SNUC), Shennongjia Nature Reserve, Xiaolongtan, VIII.2002, L.
Tang leg.; 1 3, 3 ƤƤ (IEAS), Shennongjia Nature Reserve, Muyu, 1700m, 18.VIII.1983, G.-T. Jin leg. Sichuan Province: 13 3, 7 ƤƤ, Yingjing County, Siping, VIII.2007, H.-C. Shan leg.; 7 3, 4 ƤƤ, Tianquan County, Lianglu, Erlangshan, VII.2008, X.-D. Yang leg. Anhui Province: 3 3 (CPYL, CCCC), 1 Ƥ, Dabieshan Mts., VII.2008, L. Ding leg. Zhejiang Province: 2 ƤƤ (SNUC), Lin-an County, West Tianmushan, Laodian, 1200m, IX.1999, L.-Z. Li leg.; 4 3 (CYXW), West Tianmushan, Xian-ren-ding, 1500m, IV.2008, Y.-X. Wu leg., larvae emerged in 2009; 2 3, 2 ƤƤ (SNUC), West Tianmushan, 1300m, larvae collected in IV.2009, emerged in 2010. Jiangsu Province: 1 3 (CWXB), Nanjing, VII.2003. Guangdong Province: 1 Ƥ, Ruyuan County, Nanling Reserve, 1000m, VIII.2008, X.-Y. Zhu leg. Taiwan: 14 3, 6 ƤƤ, various localities, C.-C. Chen leg.
Identification. The type series of this species was collected from Beijing, where only Prismognathus davidis has been found. Specimens from Gansu, Shaanxi, Henan, Hubei, Sichuan and northern Chongqing examined by us do not differ from the specimens from Beijing in external features and genitalia. The relatively large apex of the flagellum in male genitalia and the marked long basal portion of the spermatheca in female genitalia are markedly constant and are considered the most useful characters to recognize P. davidis.
Fujita (2010) raised P. davidis cheni to the specific rank. However the specimens of P. davidis cheni from Taiwan have most of the genitalic characters in common with the specimens from continental Chinese. Furthermore, several populations have been found to fill the gap in geographical distribution between the populations from northern and central China and those from Taiwan. The populations from Zhejiang, Jiangsu and Anhui have similar characters in male ocular canthus with the populations from Taiwan. Therefore we believe that P. davidis cheni is not a separate species.
Diagnosis. The males of P. d a v i d i s are geographically variable, with some specimens similar to those of P. klapperichi and P. dauricus; however, they are characterized in the large-sized specimens by the relatively longer mandible (different from P. klapperichi), the sinuate outer margin of the mandible (different from P. klapperichi) and the presence of the dorsal subbasal teeth of the mandible (different from P. dauricus and P. prossi). The smallsized males of P. d a v i d i s are difficult to separate from those of P. klapperichi and P. dauricus unless a dissection of genitalia is made.
The females of P. davidis are also individually and geographically variable. They are almost indistinguishable in external characters from some other species, especially the sympatric P. triapicalis and P. klapperichi. The female pronotum is usually more angled in P. d a v i d i s than in P. triapicalis, and is less transverse in P. davidis than in P. klapperichi, and the female canthus is usually narrower in P. klapperichi than in P. davidis, but all these differences are not constant and change by the localities. To identify the female of P. da v id is, a dissection is always needed. For more details see the keys below.
Several male and female specimens of P. davidis from Mt. Tianmushan, Zhejiang were identified by Wan et al. (2007) as P. klapperichi due to the similar male canthus; however we did the dissection of specimens from Mt. Tianmushan and we found that these P. klapperichi -like specimens actually belong to P. d a v i d i s. The population of P. davidis from eastern China differs from P. klapperichi by having the male mandibles more sinuous at the outer margin and the pronotum usually with less pointed lateral angles. Moreover, the mandible is only slightly longer than head in the large-sized males of P. klapperichi, whereas the mandible is about 1.5 times longer than head in the large-sized males of P. davidis. The genitalic differences between P. davidis and P. klapperichi are more remarkable: apex of the flagellum of median lobe markedly wider in P. d a v i d i s than in P. klapperichi; spermatheca and spermathecal gland of the female genitalia markedly smaller in P. davidis than in P. klapperichi; basal portion of the spermatheca markedly thinner in P. d a v i d i s than in P. klapperichi; spermathecal duct is markedly longer in P. davidis than in P. klapperichi. There are no sympatric records for these two species in Zhejiang and Fujian which have been explored by several Chinese collectors for years. Prismognathus davidis seems to be restricted to northern Zhejiang (Tianmushan) whereas P. klapperichi is known from southern Zhejiang (Fengyangshan, Baishanzu, Wuyanling) and northern Fujian (Wuyishan). The only sympatric record of these two species was from the Nanling Nature Reserve, northern Guangdong.
Subspecies. Three subspecies have been described: P. davidis davidis from northern and central China, P. davidis cheni and P. davidis nigerrimus, both from Taiwan. Prismognathus davidis nigerrimus from eastern Taiwan differs from P. davidis cheni only by a darker ground colour of the body. Herein we considered the P. davidis nigerrimus as a synonym of P. davidis cheni because the color is individually variable in most populations of Prismognathus davidis and the two subspecies were described from small areas in the same island.
The populations from Zhejiang, Anhui, Jiangsu and Guangdong have the the anterolateral angle of the head directed more laterally and less anteriorly than that of the populations from Beijing, Hebei, Shaanxi, Gansu, Henan, Hubei, Sichuan and Chongqing. However they do not merit being described as a new subspecies, as the characters of specimens are not changed synchronously by the localities. For example, the population from Anhui has the males nearly the same as those of the population from Zhejiang, but has the females nearly the same as those of the population from Beijing. Here we consider all the populations from continental China as belonging to P. davidis davidis.
Taxonomic notes. Although P. d a v i d i s is allopatric with P. dauricus and there are no external differences between their small-sized males and females, the two species are here considered as separate because of the constant differences in their male and female genitalia.
All the populations of P. d a v i d i s are considered as a single species, because all of them share the following genitalic characters: 1) apex of the flagellum in male genitalia large and wide; 2) the contracted basal portion of the spermatheca in female genitalia markedly long.
Distribution. Beijing, Hebei, Shaanxi, Gansu, Henan, Hubei, Sichuan, Chongqing, Anhui, Jiangsu, Zhejiang, Guangdong, Taiwan.
description: Published as part of Huang, Hao & Chen, Chang-Chin, 2012, A review of the genera Prismognathus Motschulsky and Cladophyllus Houlbert (Coleoptera: Scarabaeoidea: Lucanidae) from China, with the description of two new species, pp. 1-36 in Zootaxa 3255 on pages 5-7, DOI: 10.5281/zenodo.280626