Amynthas gracilis (Kinberg, 1867)

Wang, Yu-Hsi & Shih, Hsi-Te, 2010, Earthworm fauna of Eastern Taiwan, with descriptions of two new species (Oligochaeta: Megascolecidae), Zootaxa 2341, pp. 52-68 : 61

Amynthas gracilis (Kinberg, 1867)

Pheretima hawayana — Chen 1933: 238; Tsai 1964: 9; Gates 1972: 189.

Amynthas gracilis — Easton 1981: 50, 1982: 725, fig. 4b; Blakemore 2003: 19; James et al. 2005: 1024; Blakemore et al. 2006: 228; Tsai et al. 2009: 39.

Material examined. 2 adults, NCHUZOOL 13520, at streamlet near Liyu Lake, Shoufeng, Hualien Co., Taiwan, coll. Y.-H. Wang et al., 28 Jan. 2007; 1 adult, NCHUZOOL 13519, 23°11’3.6”N, 121°17’33.4”E, Luoshan Waterfall, Fuli, Hualien Co., Taiwan, coll. Y.-H. Wang et al., 1 Jan. 2005; 5 adults, NCHUZOOL 13514, 23°10’54.2”N, 121°01’22.1”E, 832.3 m, Lidao, Haiduan, Taitung Co., Taiwan, coll. Y.-H. Wang et al., 31 Dec. 2004; 6 adults, NCHUZOOL 13515, 23°10’17.7”N, 121°02’8.7”E; 709 m, Wulu, Haiduan, Taitung Co., Taiwan, coll. Y.-H. Wang et al., 31 Dec. 2004; 3 adults, NCHUZOOL 13516, 23°09’23.8”N, 121°03’32.1”E; 747.9 m, Siama, Haiduan, Taitung Co., Taiwan, coll. Y.-H. Wang et al., 31 Dec. 2004; 4 adults, NCHUZOOL 13518, Gaotai, Luye, Taitung Co., coll. Y.-H. Wang & L.-Y. Fan, 24 Oct. 2004; 2 adults, NCHUZOOL 13527, 22°02’13.5”N, 121°34’14.6”E, Yeyin, Lanyu, Taitung Co., Taiwan, coll. Y.-H. Wang et al., 1 Apr. 2008; 1 adult, NCHUZOOL 13517, Baiyu Waterfall, Jhihben, Taimali, Taitung Co., Taiwan, Y.-H. Wang & L.-Y. Fan, 22 Oct. 2004; 9 adults, NCHUZOOL 13513, Dawu, Taitung Co., coll. Y.-H. Wang et al., 30 Dec. 2004; 1 adult, NCHUZOOL 13528, 22°00’31.1”N, 121°34’17.0”E, Sihdao Ditch, Hongtou, Lanyu, Taitung Co., Taiwan, coll. Y.-H. Wang et al., 1 Apr. 2008; 6 adults, NCHUZOOL 13536, 22°02’12.2”N, 121°33’31.5”E, Lanyu Meteorological Station, Lanyu, Taitung Co., Taiwan, coll. Y.-H. Wang, 7 Jan. 2008.

Diagnosis. Dimensions 91–132 mm by 3.0– 4.7 mm in x, 2.6–4.2 mm in xxx, 2.6–4.0 mm in clitellum; body cylindrical throughout, segments 79–101. First dorsal pore at 9/10 or 10/11. Clitellum annular, xiv–xvi; setae visible on ventral in xvi or smooth. Female pore single on xiv. Male pores on xviii, 11–16 setae between male pores, 1–7 markings behind setal line. Spermathecal pores lateral at 5/6–7/8. Prostates large in xviii extending to xvi and xxii. Intestinal caeca simple, originating in xxvii, extending anteriorly to xxv.

Remarks. Gates (1972) described A. gracilis as usually having the first dorsal pore at 10/11. Easton (1981, 1982) mentioned that the spermathecal pores of A. gracilis are apart at furrows 5/6–7/8. Male pores are superficial on small porophore on xviii. Genital markings are small; clusters of up to 11 markings are median to the male pores on xviii and occasionally on xvii and xix. However, A. gracilis collected from eastern Taiwan has 1–7 markings behind the setal line of xviii, and its first dorsal pore is located at 9/10 or 10/11, which slightly differs from the descriptions of Gates (1972) and Easton (1981, 1982).