Baetiella trispinata Tong & Dudgeon, 2000

Shi, Weifang & Tong, Xiaoli, 2015, Taxonomic notes on the genus Baetiella Uéno from China, with the descriptions of three new species (Ephemeroptera: Baetidae), Zootaxa 4012 (3), pp. 553-569 : 564-566

Baetiella trispinata Tong & Dudgeon, 2000

( Fig. 53 )

Baetiella trispinata: Tong & Dudgeon, 2000: 145

Diagnosis. Posterior margin of metanotum and abdominal terga I–III each with a finger-like mediodorsal protuberance, terga IV–IX each with a pair of protuberances decreasing in length towards apex ( Fig. 53 ). All legs without coxal gills; tarsal claw with two rows of denticles, outer row with 6–7 acute denticles increasing in length towards apex, inner row with 4–5 short and blunt denticles medially. Hind wing pads vestigial. Gills present on terga I–VII. Median caudal filament with only one segment.

Type material examined. Holotype (in ethanol, deposited in SCAU): China. Hong Kong: Ma Po Mei, Lam Tsuen River near Lam Kam Road, 29.x.1997, leg. Xiaoli Tong. Paratypes (in ethanol, deposited in SCAU): China, Hong Kong: 1 female and 2 male imagoes, 7 nymphs, same data as holotype; 2 nymphs, Tai Po Kau Forest stream, 25.ii.1999, leg. Xiaoli Tong; Guangdong: 6 nymphs, Huizhou, Nankunshan Nature Reserve, near the Middle School, 16.ix.1994, leg. Xiaoli Tong; 3 nymphs, Yangshan County, Chenjia Forest Farm, Lutian, 15.vii.1996, leg. Xiaoli Tong.

Other material examined (deposited in ethanol unless otherwise stated). CHINA. Hunan: 5 nymphs, Yanling County, Shennong Vally Scenic, Taohuaxi, 12.xii.2013, leg. Weifang Shi; Jiangxi: 3 nymphs, Jiulianshan National Nature Reserve, Xiagongtang (26.37°N, 114.93°E, alt. 230m), 30.iv.2010, leg. Xiaoli Tong; 3 nymphs, Anfu County, Taishan Town, Wenjia, Wugongshan Scenic, 8.xii.2013, leg. Weifang Shi; 1 nymph, Lianhua County, Gaozhou Town, Huangsha, 10.xii.2013, leg. Weifang Shi; Guangxi: 43 nymphs, Shangsi County, Shiwandashan Forest Park (21.90°N, 107.90°E, alt. 320m), 29.ix.2011, leg. Weifang Shi; Guangdong: 117 nymphs, Xinyi, Tianmashan Scenic (22.47°N, 110.64°E, alt. 470m), 2.iv.2011, and 1 nymph on slides and 12 nymphs, the same locality but collected on 19.ix.2011, leg. Weifang Shi; 9 nymphs, Yingde, Shimentai Nature Reserve, Hengshitang (24.41°N, 113.31°E, alt. 150m), 7.iv.2011, leg. Weifang Shi; 2 nymphs, Dongguan, Yinpingshan Forest Park (22.90°N, 114.21°E, alt. 130m), 19.vii.2011, leg. Weifang Shi; 1 nymph on slides and 41 nymphs, Heyuan, Yequgou Scenic (23.71°N, 114.62°E, alt. 210m), 24.viii.2011, and 132 nymphs, the same locality but collected on 14.ix.2011, leg. Weifang Shi; 8 nymphs, Huizhou, Xiangtoushan Nature Reserve (24.08°N, 110.23°E, alt. 810m), 21.iv.2012, leg. Weifang Shi.

Distribution. China (Hunan, Jiangxi, Guangxi, Guangdong, Hong Kong, Hainan).

Comments. B. trispinata Tong & Dudgeon shares morphological affinities, particularly in the claw with two rows of denticles, not only with B. bispinosa (Gose) , but also with B. macani (Müller-Liebenau) ; however, it can be easily distinguished from them by the abdominal terga I–III each with a single posteromedial dorsal protuberance, terga IV–IX each with a pair of protuberances, and all legs without coxal gills. This species is widely distributed in southern China (from Hunan Province, through Guangxi, Guangdong to Hainan). The nymphs mainly inhabit on the surface of stones in rapidly-flowing streams.

Figures

FIGURES 45 – 54. Baetiella spp. from China. (45) B. bispinosa (Gose); (46 – 47) dorsal and lateral view of B. macani (Muller- Liebenau); (48) B. marginata Braasch; (49) coxal gills of B. macani (Muller-Liebenau); (50) thoracic sterna of B. spathae n. sp.; (51) thoracic sterna of B. tuberculata (Kazlauskas); (52) head and thorax of B. marginata Braasch; (53) B. trispinata Tong & Dudgeon; (54) B. tuberculata (Kazlauskas).