Gammarus lacustris Sars, 1863

Hou, Zhong-E & Li, Shuqiang, 2005, Amphipod crustaceans (Gammaridea) from Beijing, P. R. China, Journal of Natural History 39 (36), pp. 3255-3274 : 3257-3258

Gammarus lacustris Sars, 1863

Gammarus lacustris Sars 1863, p 207 ; Pinkster 1972, p 166 –169; Karaman and Pinkster 1977, p 32 –34; Barnard and Dai 1988, p 92 –94.

Gammarus pulex: Dahl 1915, p 1 –32.

Gammarus scandinavicus: S. Karaman 1931, p 101 .

Gammarus bolkayi: S. Karaman 1934, p 325 .

Gammarus (Rivulogammarus) lacustris: Schellenberg 1937, p 490 .

Rivulogammarus lacustris: Dussart 1948, p 101 –102; Straskraba 1967, p 208.

Gammarus lacustris lacustris: Bousfield 1958, p 80 .

Gammarus wigrensis: Micherdzinski 1959, p 598 –599.

Material examined

Zhenzhuquan Spring , Caishihe River , Yanqing County: six males and seven females, 26 August 2001, collected by Shuqiang Li and Guoqing Zhang. Badaohe River , lower reaches of Baihepu Reservoir , Yanqing County, collected by Shuqiang Li and Guoqing Zhang : 36 males, 21 females and 12 juveniles, 26 August 2001; one female, 26 August 2001; 167 males, 116 females and 35 juveniles, 7 April 2004. Maquan Spring, Shangbanquan Town , Yanqing County : 11 males and 17 females, 26 August 2001, collected by Shuqiang Li and Guoqing Zhang. Fengsui Relic, Xiabanquan Village, Yanqing County : one female, 18 May 2004, collected by Shuqiang Li and Zhong-E Hou. Guanting Reservoir , Heilongmiao Village, Yanqing County, collected by Shuqiang Li and Zhong-E Hou: one male and one female, 18 May 2004; two females, 18 May 2004; 29 males, 30 females and two juveniles, 18 May 2004; 47 males and 47 females, 18 May 2004. Beiganchi Village, Changgou Town, Fangshan District: two males, 7 December 1992; 101 males, 97 females and 28 juveniles, 15 September 2001, collected by Yuezhao Wang and Shuqiang Li. Xiganchi Village, Changgou Town, Fangshan District : 123 males, 121 females and five juveniles, 15 September 2001, collected by Yuezhao Wang and Shuqiang Li. A spring from Shidu Scenic Area , Fangshan District: 97 males, 163 females and 29 juveniles, 12 May 2000, collected by Shuqiang Li. Qingshuihe River , near Xihulin Village , Mentougou District, collected by Shuqiang Li and Kaibaryer Meng : two males and one female, 13 October 2001; six males and three females, 13 October 2001. Zhenzhu Spring: one male, September 1994, collected by Yixiong Cai.

Diagnosis

Body large and stout; peduncle of antenna 2 with few short setae, calceoli present in male; pereopods 3 and 4 with long straight setae on posterior margins; epimeral plates 2 and 3 with sharp posterodistal corners; inner ramus of uropod 3 reaching about 75% of length of outer ramus, both rami set with plumose setae.

Remarks

Gammarus lacustris was redescribed by Karaman and Pinkster (1977) based on samples from all over its distributional area, while Barnard and Dai (1988) redescribed it in detail with material from Yunnan, China. The material examined from Beijing accords well with the figures and description of G. lacustris given by Barnard and Dai (1988), except that the bases of pereopods 5–7 are a little more elongate, epimeral plates 2 and 3 without very sharp posterodistal corners and telson with one basolateral spine.