Amynthas phaselus maculosus (Hatai, 1930: 661)

Blakemore, Robert J., 2013, Jeju-do earthworms (Oligochaeta: Megadrilacea) - Quelpart Island revisited, Journal of Species Research 2 (1), pp. 15-54 : 31

Amynthas phaselus maculosus (Hatai, 1930: 661)

comb. nov. [ Fig. 10 ]

Material examined. IV0000261231 mature specimen collected from besides a stream near Sanbansan SW Jeju, 12 th June, 2012 by RJB - a mature that was figured and dissected, providing DNA samples ( WO 51 redone as w27). Included in same jar is a tail portion.

Description. (Jeju specimen). Length 100 mm. Segments

99. Colour brownish, clitellum buff. First dorsal pore 11/ 12. Genital markings absent. Setae ca. 36 on segment 10. Spermathecae ca. 0.3 C apart in 5/6/7/8. Male pores superficial on 18 with 12 setae intervening. Septa 8/9/10 are aborted around gizzard. Spermathecae in 6-8 with elongate and corrugated ampulla on shorter duct with clavate diverticulum. Hearts are in 13. Holandric: testis in 10 & 11, seminal vesicles in 11 & 12 the latter pair with finger-like dorsal projections. Ovaries in 12, no ovisacs. Prostates large in 18. Oesophagus dilated in 11-13. Intestinal origin in 15, no typhlosole to about 35. Gut contains mainly soil.

Remarks. The current specimen agrees with earlier descriptions of Amynthas kamitai ( Kobayashi, 1934) from Jeju that appears now to correspond with A. maculosus (Hatai, 1930) from northern Japan, that itself was previously included in synonymy with A. phaselus (Hatai, 1930) , e.g. by Blakemore (2008). A. maculosus was revived based on a Tokyo syntype by Blakemore (2012: 113, fig. 12). Its new synonyms are Pheretima kamitai Kobayashi (1934: 5 , figs. 4-6; 1938: 146, fig. 11) that was from Seoul and latterly included Ph. serrata Kobayashi (1936: 165 , text fig. 10) in synonymy. Referred to as Ph. phaselus var. kamitai by Kobayashi (1938: 411) and by Song & Paik (1969: 16, 1970: 11) on specimens from Hokkaido and Jeju, respectively. Since nothing of substance separates Amynthas minjae Hong, in Hong, Lee & Kim (2001) from these prior taxa, it too is included in synonymy. Reduced to a sub-species of the nominal taxon, the question of its relationship to A. phaselus is not fully resolved. This Jeju specimen (initially thought similar to A. gracilis ) complies with A. maculosus , or rather its synonym A. kamitai , more so than with A. phaselus proper.

Figures

Fig. 10. Amynthas phaselus maculosus (Hatai, 1930: 661). Ventral view with prostomium, spermathecae and prostates in situ; caeca 27rhs.