Ephemera (Sinephemera) axillaris Navas 1930

Ephemera (Sinephemera) axillaris Navás, 1930 (Figs 1–5, 64) Ephemera axillaris Navás, 1930: 138, adults (sex undeclared; from China). Ephemera axillaris — Wu, 1935: 247; Ulmer, 1935–1936: 212; Hsu, 1936: 146 (adult); Gui, 1985: 93; You et Gui, 1995: 112 (male imagine); Zhang & You, 1995: 74; Hwang et al., 2008: 160 (list); Zhou et al., 2015: 232 (list); Kluge, 2004: 237 (list, subgenus incertae sedis). Ephemera hsui Zhang & You, 1995: 75 (male and female imagine, male and female subimagine). Types: male, female, subimagine, Dayong and Zhang-Jia-Jie, Hunan. Syn. nov. Ephemera hsui — You et Gui, 1995: 104 (male, female imagine); Zhou et al. 1998; Zhou et al., 2003: 69 (first description of nymph); Zhou, 2013: 184 (list); Hwang et al., 2008: 161 (list). Syn. nov. Description (see Zhang et al., 1995 and Zhou et al., 2003). Diagnosis: Mature nymph: (1) Two mandibular tusks subequal in length, longer than head (Figs 1A–E); (2) length of frons 1.5–2.0x width; lateral margins of frons almost straight, anterior margin of frons shallowly to deeply forked (Figs 1A, C, E). (3) Both fore and hind wingpads with distinct black dots and markings, especially near margins (Fig. 1A). (4) Abdominal tergites I–II with very short median spines on posterior margin (Fig. 1F). (5) Gill I–V located at posterolateral angles of tergites, gills VI–VII at middle or slightly nearer to anterolateral angle. (6) Stripe pattern on abdominal tergites (Figs 1A, C): tergites I–II with pair of very oblique stripes, sometimes those stripes near posterior margin and very wide, making them crescent shaped. Tergites III–IX with three pairs of straight stripes, median one or sometimes median two ones narrowed anteriorly. Tergite X without stripes. (7) Sternites IV–IX or V–IX with pair of nearly straight black stripes respectively, those stripes progressively longer from anterior to posterior (Figs 1B, D). (8) Posterior and lateral margins of tergites with reddish or deep reddish lines (Figs 1A, C). Male imagine: (1) Tergites and sternites of abdomen with stripes similar to that of nymph (Figs 2–3). (2) Forefemur deep brown, other parts of foreleg black brown; foretibia slightly longer than tarsus, forecoxa with a black stripe (Figs 2A, 3B, 4D); midcoxa with a black stripe too (Figs 2A, 3B, 4E); hindleg pale (Figs 2A, 3B, 4F). (3) Forewings with distinct median stripes (Figs 2A, 4A), most crossveins of stigmatic area branched (Fig. 4A); A 1 with 15 veinlets (Fig. 4B); posterior margin of hindwing tinged with brown to deep brown (Figs 2A, 4C). (4) Abdominal tergites I–II slightly humped up medially (Fig. 4G). (5) Basal 1/3 of forceps reddish to reddish brown, apical 2/3 chocolate brown to black; segments III–IV subequal in length, both relatively short (Fig. 4H). Penes located agaist each other (without median separation space between them), apices divergent and slightly expanded (Figs 4H–I). Outer half of penes sclerotized. Female imagine: (1) Tergites and sternites of abdomen with stripes similar to that of male or nymph, but stripes usually paler and narrower (Figs 2B, 3D–F). (2) Legs ocher but apex of forefemur, tibia and tarsus brown (Figs 5A–C); forecoxa with a brown dot (Fig. 5A). (3) Less stigmatic crossveins branched than in males (Fig. 5D) and crossveins with less pigments (Figs 5D–E). Comparison: the color pattern of this species is very close to that of E. purpurata Ulmer, 1919. Both of them have oblique markings on tergites I–II and three pairs of longitudinal stripes on tergites III–IX (Figs 3, 43). But E. purpurata has reddish markings on its hindwings (Figs 42A–B, F, 44E), which is not so in E. axillaris (Figs 2, 4C, 5E), and the stripes on tergites I–II of E. purpurata are usually separated (Figs 43A, C) in contrast to fused in E. axillaris (Fig. 3). These two characters can also be used to separate their nymphs and females. Besides, the color pattern of this species is similar to some Ephemera s. str. species, such as E. rufomaculata Zhou and Zheng, 2003 or E. orientalis McLachlan, 1875. But the markings on tergites I–II of the latter two species are never crescent, usually are two independent patches or square markings. The male genitalia of this species is close to that of Ephemera rubera sp. nov., since penes are longer than segment I of forceps, and their apices are slightly widened (Figs 4H–I and Figs 47E–F). But the penes of E. rubera sp. nov. are slightly longer than in E. axillaris, and their color on body and wings are quite different, the E. rubera sp. nov. is much more colorful and redder than E. axillaris. Remarks: Navás (1930) described this species briefly and provided a partial figure of its abdominal stripes on tergites. Hsu (1936) copied those descriptions in his review. This makes it extremely difficult to identify. However, based on three key features (crescent markings on tergites II, as in the figure of Navás, 1930; three pairs of straight stripes on the remaining segments, the inner pair convergent anteriorly; vein A 1 of forewing with more veinlets), we associated our materials to this species. Zhang et al. (1995) established Ephemera hsui based on adults, Zhou et al. (1998) described its nymphs. After checking the types and related materials, this species is synonymized to the E. axillaris here upon three key characters mentioned above. Material examined: China: 1 ♂ imagine (holotype of Ephemera hsui), Zhangjiajie, Dayong county, Hunan province, leg. Jun Zhang & Shu-Sheng She, 1986-VI-20; 1 ♂ and 1 ♀ imagine (paratypes of Ephemera hsui), same as the former; 8 nymphs, Bao-Mu-Ping village, Shaoyang county, Hunan province, leg. Zhen-Xing Ma, 2020-VIII-24; 1 ♀ imagine, Yingzuijie, Huitong county, Hunan province, leg. Jian-Hua Huang, 2022-VIII-02; 6 nymphs, Shanqi village, Hetan town, Xinghuang county, Hunan Province, leg. Peng Li & Jia-Yong Zhang, 2004-VIII-11; 1 ♂ and 11 ♀ imagines, Hutiao gorge, Lijiang municipality, Yunnan province, leg. Bei-Xing Wang & Chang-Fa Zhou, 1996-V-26; 5 ♀ imagines, 10 nymphs, Yangceng river, Yangceng town, Jianchuan county, Yunnan province, leg. Hui Xie, Yan-Yan Jia & Ping Chen, 2008-VII- 14; 1 ♀ imagines, Lusaihe village, Luku town, Lushui county, Yunnan province, leg. Cheng-Bing Wang, 2019-VII- 11; 1 ♂ and 2 ♀ imagines, Lamengga river, Lushui county, Yunnan province, leg. Xu-Hong-Yi Zheng & Zhen-Xing Ma, 2022-VI-30; 5 ♀ imagines, 5 nymphs, Baijing town, Huishui county, Guizhou Province, leg. Chang-Fa Zhou & Chuan-Ren Li, 2000-IX-12; 6 ♂ and 2 ♀ imagines, Jingsha valley, Suoluo protection, Guizhou Province, leg. Chang-Fa Zhou & Chuan-Ren Li, 2000-IX-22; 2 ♂ and 1 ♀ imagines, 1 ♀ subimagine 1 nymph, Wuxing village, Xishui county, Guizhou Province, Hai-Li Yu & Chang-Fa Zhou, 2000-IX-28; 2 ♀ imagines, 20 nymphs, Wudong village, Leishan county, Guizhou Province, leg. Zhen-Xing Ma & Xu-Hong-Yi Zheng, 2019-VII- 30; 5 ♂ and 10 ♀ imagines, Wuquan town, Suiyang county, Guizhou Province, Lu-Yu Wang, 2020-IX-8; 4 nymphs, Lanying valley, Yingtiaoling Mt., Chongqing municipality, leg. Peng-Xu Mu, 2022-VIII-16; 1 ♂ and 2 ♀ imagines, 1 nymph, Huang-Cao-Ping village, Chongqing municipality, Chuan-Ren Li & Chang-Fa Zhou, 2000-IX-3; 7 nymphs, Daqiutian, Jiulianshan Mt., Longnan county, Jiangxi province, leg. Chang-Hai Sun & Chang-Fa Zhou, 2005-VI-10; 1 nymph, Leigulin, Wuyi Mt., Jiangxi province, leg. Lian-Fang Yang & C. Geraci, 2005-VI-4; 1 ♀ imagine, Shenziping village, Renheping town, Wufeng county, Hubei province, leg. Dai Zhou, 2013-VII- 11–14; 1 ♂ and 2 ♀ imagines, 4 ♂ and 4 ♀ subimagines, 20 nymphs, Fulushanzhuang village, Muyu town, Hubei province, leg. De-Wun Gong, 2023-VI-15 – 16; 1♂ and 1 ♀ imagines, 10 nymphs, Mudan Hotel, Dujiangyan city, Sichuan Province, leg. Chang-Fa Zhou, 2005-VII- 10; 2 ♂ and 1 ♀ imagines, Woqiwo village, Longwu town, Meigu county, Sichuan Province, leg. Chang-Fa Zhou, 2005-VII- 6; 1 ♂ and ♀ imagines, Xilin scene, Chendu city, Sichuan Province, Xu-Hong-Yi Zheng & Peng-Xu Mu, 2021-VII- 14; 6 ♀ imagines, Longchang valley, Yingjing county, Sichuan Province, leg. Xu-Hong-Yi Zheng, Peng-Xu Mu, 2021-VII- 21; 3 ♂ imagines, 1 nymph, Qinghe forestry, Kangxian county, Gansu Province, leg. Chang-Fa Zhou, 2000-VIII-24; 1 ♂ and 10 ♀ imagines, Hongxing village, Ankang county, Shaanxi Province, leg. Hai-Li Yu, 2003-VII- 3–5; 6 ♂ and 10 ♀ imagines, 8 nymphs, Yueba village, Fuoping county, Shaanxi Province, leg. Chang-Fa Zhou, 2000-VII- 25; 10 ♂ and 3 ♀ imagines, 5 ♂ and 5 ♀ subimagines, Xunyangba town, Ningsha county, Shaanxi Province, leg. Jiang-Hua Dai, 2014-VIII-13–18; 2♀ imagines 1 nymph, Dabancha village, Xi’an city, Shaanxi Province, leg. Zhao Xie & Shen Xu, 2012-V; 3 ♂ and 10 ♀ imagines, 2 ♂ and 5 ♀ subimagines, 10 nymph, Baiyun Mt., Songxian county, Henan Province, Wei Zahng, Xiao-Li Ying & Ming Zhang, 2020-VII- 15; 1 ♂ and 2 ♀ imagines, Shiziping village, Henan Province, Dan-Dan Zhang, 2001-VII- 20; 1 ♀ imagine, Baligou valley, Xingxiang city, Henan Province, leg. Peng Li & Chang-Fa Zhou, 2004-VII- 10–11, 5 ♂ imagines, 3 ♂ and 2 ♀ subimagines, 30 nymphs, Tianchi Mt., Songxian county, Henan Province, leg. Peng Li & Chang-Fa Zhou, 2004-VII- 12–13; 1 ♂ and 3 ♀ imagines, 10 nymph, Baiyun Mt., Songxian county, Henan Province, leg. Peng Li & Wei-Xing Liu, 2004-VII- 14–18; 5 ♀ imagines, 2 nymphs, Longyu valley, Luanchuan county, Henan Province, leg. Peng Li & Wei-Xing Liu, 2004-VII- 19–21; 4 ♂ and 20 ♀ imagines, 5 ♂ and 10 ♀ subimagines, Baotianman scene, Neixiang county, Henan Province, leg. Peng Li & Wei-Xing Liu, 2004-VII- 22–25; 8 ♂ and 10 ♀ imagines, 3 ♂ and 5 ♀ subimagines, 10 nymphs, Xihonghong village, Henqu county, Shanxi Province, leg. Dong Liu & Zhaofeng Wang, 2006-VIII-2; 4 ♀ imagines, 10 nymphs, Zhuwei valley, Zhongcun town, Qingshui county, Shanxi Province, leg. Yan-Xia Wang & Ze-Yu Wang, 2012- VII-23; 1 ♂ and 1 ♀ imagines, Nuying valley, Xiachun village, Zhongchun town, Qingshui county, Shanxi Province, leg. Chang-Hai Sun, 2013-IX-11; 2 ♀ imagines, 20 nymphs, same loc