Metaphire magna minuscula Qiu & Zhao

Zhao, Qi, Jiang, Jibao, Sun, Jing & Qiu, Jiangping, 2013, Four new earthworm species and subspecies belonging to genus Amynthas and Metaphire (Oligochaeta: Megascolecidae) from Hainan Island, China, Zootaxa 3619 (3), pp. 383-393 : 388-390

Metaphire magna minuscula Qiu & Zhao , subsp. nov.

( Fig. 4 , Table 2 )

Material. Holotype one clitellate (F-HN 201116 fm) (fm=formalin), China, Hainan Province, Longmeng Town (19°26ʹ44ʺ N, 110°22ʹ18ʺE), 101m a.s.l., soil, coll. J.P. Qiu, Q. Zhao, J.B. Jiang, D. Cluzeau and W.K. Zhang, 27 May 2011. Paratype one clitellate (C-HN 201116 -01), same data as for holotype.

Locality and habitat. The specimens were collected under rubber plantation of Longmeng Town, Tunchan City, Hainan province, China.

Etymology. This subspecies’ name indicates that it is smaller than Metaphire magna magna .

Diagnosis. Dimensions?– 297 mm by 10–12 mm at clitellum, segments?–137. Setae 36– 46 /III, 44– 46 /V, 52– 56 /VIII, 40–60/XX, 52–78/XXV; 0–11 between male pores; 12–20 between spermathecal pores. Spermathecal pores in 7/8–8/9, about 0.4 circumferences ventrally apart. Male pores on XVIII, a little longer than 0.3 body circumferences apart, ventrally placed in a copulatory pouch, surrounded by three to four circular folds.

Description. Preserved specimens dark brown on dorsum, light brown ventrally. Dimensions? – 297 mm by 10–12 mm, segments? –137; body cylindrical in cross-section, gradually tapered towards head and tail. Prostomium epilobous. Setae numbering 36– 46 /III, 44– 46 /V, 52– 56 /VIII, 40–60/XX, 52–78/XXV; 0 between male pores; 12–20 between spermathecal pores, setal formula AA=1.2–1.5AB, ZZ=1–2ZY. Clitellum annular XIV–XVI, markedly glandular, dark brown; setae cannot be seen externally in clitellum. First dorsal pore in 11/12. Two pairs of spermathecal pores in 7/8–8/9, ventral, eye-like and obvious, about 0.4 body circumferences apart. Genital markings not present. Male pores are paired in XVIII surrounded by three to four circular folds, a little longer than 0.3 body circumferences ventrally apart, each in a copulatory pouch. Genital papillae not present. Female pore single in XIV.

Septa 5/6–7/8 comparatively thick and muscular, 10/11–12/13 thin, 8/9 thin, membranous, 9/10 absent. Dorsal blood vessel single, continuous onto pharynx; esophageal hearts in X–XIII, the first pair is small. Gizzard in IX–X, ball-shaped; intestine enlarged distinctly from XVI; intestinal caeca simple, originating in XXVII and extending forward to XXIV, with distinct teeth-shaped incision on dorsum, smooth ventrally. Spermathecae paired in VIII–IX, 3 mm long; ampulla heart-shaped, about 2.5 mm long, spermathecal duct as long as 0.2 main pouch; diverticulum a little longer than main pouch by 0.2 mm, weakly bent in zigzag fashion or U-curved, terminal 0.67 enlarged as a clavate seminal chamber; no nephridia on spermathecal ducts. Male sexual system holandric, testis sacs two pairs in X–XI; seminal vesicles paired in XI –XII, developed, ventrally separated; prostates in 2/3XVII–2/ 3XIX, small but stout, closely adherent to body wall, prostatic duct U-shaped. Accessory glands lacking.

80 Metaphire wuzhimontis sp. nov. 38 Metaphire schmardae

Metaphire magna magna

33 95 Metaphire magna minuscula subsp. nov.

Metaphire tschiliensis tschiliensis

Metaphire yuhsii

100 59

99 Metaphire formosae

52 Metaphire bununa

Metaphire californica

Lumbricus rubellus

Lumbricus terrestris

0.0 1 Remarks. Our specimens agree with the diagnosis of Metaphire magna (Chen, 1938) in the following characteristics: body colour dark, setal formula, two pairs of spermathecal pores in 7/8–8/9, septa in 8/9 membranous, distinct teeth-shaped intestinal caeca, and type of spermathecae. However, our specimens are much smaller than described for M. magna , setae are fewer, and there is no accessory gland. In view of the slight but nonetheless clearcut differences, we decided to give subspecies status to our specimens. Our result is confirmed by the NJ tree and K2P distances of all the Metaphire species in China mainland, Taiwan Island and Hainan Island ( Figure 5, Table 2 ). Distance of COI between Metaphire magna minuscula and Metaphire magna magna was 16%, and those between Metaphire magna minuscula and other Metaphire species were nearly or more than 20%. The same pattern appeared in the distances of combined COI and 16S sequences among Metaphire species: 12% between Metaphire magna minuscula and Metaphire magna magna , and nearly or more than 15% between Metaphire magna minuscula and other Metaphire species ( Table 2 ). The sequences of COI and 16S gene of both Metaphire magna minuscula subsp. nov. (C-HN 201110 -01) and Metaphire magna magna (C-HN 201112 -01) have been deposited in GenBank ( Table 1 ). A morphological comparison of Metaphire magna minuscula with other Metaphire species with spermathecal pores in 7/8–8/9 from China and Southeast Asia is given in Table 3.

Figures

FIGURE 4. Metaphire magna minuscula subsp. nov. A. Ventral body surface with spermathecal pores. B. Spermatheca. C. Ventral body surface with male pores. D. Intestinal caeca.

Tables

TABLE 2. K 2 P distances of COI sequences (top right) and combined COI and 16 S sequences (bottom left) among Metaphire species in China mainland, Taiwan Island and Hainan Island.

	(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)	(11)
(1) Metaphire wuzhimontis		0,218	0,208	0,231	0,199	0,184	0,216	0,202	0,209	0,239	0,238
(2) Metaphire magna magna	0,153		0,163	0,197	0,224	0,185	0,213	0,200	0,191	0,226	0,248
(3) Metaphire magna minuscula	0,145	0,124		0,224	0,214	0,193	0,213	0,198	0,203	0,234	0,266
(4) Metaphire californica	0,159	0,152	0,163		0,254	0,190	0,192	0,195	0,175	0,241	0,249
(5) Metaphire schmardae	0,131	0,155	0,147	0,174		0,192	0,213	0,184	0,195	0,257	0,252
(6) Metaphire tschiliensis tschiliensis	0,137	0,149	0,143	0,154	0,136		0,141	0,120	0,132	0,210	0,241
(7) Metaphire formosae	0,159	0,168	0,165	0,148	0,168	0,132		0,126	0,108	0,208	0,238
(8) Metaphire bununa	0,154	0,149	0,152	0,156	0,149	0,120	0,100		0,129	0,229	0,244
(9) Metaphire yuhsii	0,157	0,155	0,155	0,141	0,150	0,127	0,094	0,095		0,206	0,234
(10) Lumbricus rubellus	0,219	0,221	0,222	0,223	0,225	0,205	0,209	0,223	0,206		0,211
(11) Lumbricus terrestris	0,215	0,234	0,240	0,225	0,225	0,229	0,233	0,240	0,231	0,161