Drawida koreana koreana Kobayashi, 1938

Blakemore, Robert J., Lee, Seunghan & Seo, Hong-Yul, 2014, Reports of Drawida (Oligochaeta: Moniligastridae) from far East Asia, Journal of Species Research 3 (2), pp. 127-166 : 143-144

12. Drawida koreana koreana Kobayashi, 1938

Drawida koreana Kobayashi, 1938: 102 , fig. 3 (from Kyôjô, etc. Types not known); Kobayashi, 1940: 268; 1941: 515; Easton, 1981: 35, 39; Blakemore, 2012b; 2013: 125.

Distribution. Originally described on 150 or so specimens ranging from “Kyôjô” (present day Kyojo, Hamgy̆ong- Bukto) in NE North Korea to “Ryûjin” which is close to present-day Suwon in Gyeonggi-do which means ‘the area surrounding the capital (Seoul)’ in NW South Korea. Kobayashi (1940: 311) obtained D. koreana in “ centraleastern district of Manchoukuo [=present day Dongbei]” as well as from northern and central Korea. Kobayashi (1941) reported it from Kyushu, Japan.

Description. Dark blue or dark reddish blue dorsally, lighter ventrally, clitellum pinkish. Length 63-100 mm, to 4 mm, with 130-186 segments. Prolobous. Dorsal pores absent. Setae paired (ab=cd). Clitellum 10-13. Spermathecal pores in 7/ 8 in c-lines. Male pores on nipple-like conical porophore posteriorly on 10 overhanging 10/ 11 in bc but nearer c-lines. Female pores anterior of 12 in b-lines. GM papillae present irregularly on 7-12 with glands internally.

Septa 5/6-7/8 thickened; 10/11 and 11/12 meet dorsally. Spermathecal ampulla spherical, duct very short and thick joins side of small atrium near base. Testis sacs in 9/10, vas deferens short entering body wall near thick and short prostate gland (the glandular part easily removed around its tubular body). Ovaries in chamber of 10/11/12, oviducts extend up to 22. Gizzards two or three in 12-13, 14.

Remarks. Said by Kobayashi (1938) to differ from pale coloured D. japonica and its synonym D. propatula Gates, 1935 in the larger aspect of the male pore (more stubby) and shorter, thicker spermathcal duct. As noted by Blakemore (2013a), D. koreana is seemingly a variable species or perhaps a species-complex. Types of D. koreana are missing and topotypic neotypification is difficult due to restricted access to North Korea, in particular to the sanctuary of the Ri dynasty mausoleum at Kyojo that Kobayashi (1938: 91) indicated may be the type-locality. Thus a pragmatic solution, pending full determination of the nominal taxon, is to describe new sub-species, such as the next three taxa, that are unambiguously identifiable on their DNA (Appendix, Fig. 1).

Blue and/or red coloured Drawida willsi Michaelsen, 1907 that is ca. 60 mm long is a dominant earthworm in Indian crop fields and rice paddy, also widely distribut- ed as a vermicomposing species there and often used for ecotoxicology studies. [Note that D. hattamimizu is also reddish when subadult and dark bluish when mature]. It differs only in detail (e.g. spermathecal pores in ab-lines and longer spermathecal duct perhaps, with GMs in 9/10) and requires separation based on its DNA profile too. Gizzards in D. willsi were said by Michaelsen (1907: 145; 1909: 144) to occur in 13,14-15, but Gates (1945: 215) had 1,600 specimens with two to four gizzards in some of 12-16, as in D. koreana . Michaelsen (1909: 117, 146) pointed out that it was similar, if not synonymous, to his earlier D. japonica that typically had gizzards in 12-13 only. Male pores in D. willsi are in b-lines, spherical equally in 10 and 11 with a small conical porophore that may resemble that for D. koreana but, unfortunately, no figure is available. Rudimentary male pores are also often present in 9/10 and thus it was thought a transitional species. Resolution of the relationship of these taxa requires further work.