Amynthas shinjiroi, Wang, Yu-Hsi & Shih, Hsi-Te, 2010

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 : 53-56

Amynthas shinjiroi sp. nov.

( Fig. 2 )

Material examined. Holotype: 1 adult, NCHUZOOL 13507, 29 K Rueisuei Forest Trail, Jhuosi, Hualien Co., Taiwan, coll. Sheng-Hai Wu, 15 Feb. 1997. Paratypes: 12 adults, NCHUZOOL 13543, same collection data as for holotype.

Others. 9 adults, NCHUZOOL 13508, same collection data as for holotype.

Description. External: Dimensions 95 mm by 4.2 mm in x, 3.2 mm in xxx, 4.3 mm in clitellum; body cylindrical throughout, segments 106. Setae regularly distributed around segmental equators; 11 setae between male pores; setal formula AA: AB: YY: YZ = 1.25: 1: 2.75: 2.5 on xxv. Prostomium, pro-epilobic. Unpigmented. First dorsal pore at 5/6. Clitellum annular, xiv–xvi, smooth. Female pore single on xiv. Male pores on xviii ( Fig. 2 a).

Male pores without genital marking, but with many small genital markings in front of setal line of xvii, xviii, and xix ( Fig. 2 a). Spermathecal pores ventrolateral at 5/6–8/9, with many small genital markings present in front of setal line of viii and ix ( Fig. 2 a).

Internal: Septa, 5/6–8/9 thin, 9/10–10/11 thin, 11/12 absent, 13/14–16/17 thin; gizzard in viii–x. Intestinal origin from xvi; lymph glands present from xvi; typhlosole simple 1/10 lumen diameter from xxi, but extending forward as a small ridge to xvi. Intestinal caeca simple, originating in xxvii, extending anteriorly to xxiv ( Fig. 2 d). Oesophageal heart absent, no heart in x or xi.

Male sexual system holandric, testes, funnels ventrally joining sacs in x and xi. Seminal vesicles large in xi and xii, with dorsal lobe. Prostates in xviii, 6 main lobes, ducts thick, muscular; many small accessory glands ( Fig. 2 c).

Ovaries in xiii. Spermathecae paired in vi–ix, ampulla with elongate ovoid diverticulum; diverticulum axis longer than ampulla axis; many small accessory glands in viii and ix ( Fig. 2 b).

Etymology. This species is named for the Japanese zoologist Shinjiro Kobayashi, who contributed much to the study of earthworm diversity of Taiwan during 1938–1941 (see Shih et al. 1999).

Remarks. Amynthas shinjiroi sp. nov. is similar to A. omeimontis ( Chen, 1931) , A. polyglandularis ( Tsai, 1964) and A. tessellatus Shen, Tsai & Tsai, 2002 , but can be distinguished by several characters. Chen (1931) described A. omeimontis from Ermei (= Omei) Mt., Ermei Co., Sichuan Province, China, with small genital markings on xi and xviii, and the male pore is surrounded by genital markings, which are absent on xvii and xix. Tsai (1964) described A. polyglandularis from Taipei, Taiwan, which also has small genital markings on viii–ix and xviii, and the male pore is also surrounded by genital markings. Shen et al. (2002) described A. tessellatus tessellatus and A. tessellatus paucus from Nantou and Hualien Cos., Taiwan, with small genital markings on vi–ix and xvii–xix segments; the male pore lacks genital marking. In addition, A. shinjiroi has 4 spermathecal pores at 5/6–8/9, and the first dorsal pore is at 5/6. However, A. omeimontis and A. polyglandularis have 2 pairs of spermathecal pores at 7/8–8/9 and the first dorsal pore is at 12/13; and A. tessellatus has 3 spermathecae in vi–viii, and the pores are not visible; the first dorsal pore is at 11/12. A comparison of characters is given in Table 1 .

Figures

FIGURE 2. Amynthas shinjiroi sp. nov. (holotype, NCHUZOOL 13507); a, ventral view of spermathecal pores in segment furrows and small genital markings on viii and ix; male pores with many small genital markings on xvii, xviii, and xix; b, right spermathecae and small accessory glands; c, right prostate and small accessory glands; d, right intestinal caeca. ag, accessory gland; amp, ampulla; dv, diverticulum; fp, female pore; gm, genital marking; mp, male pore; sp, spermathecal pore. All scale bars are 1 mm.