Eisenia japonica vaga Blakemore, 2013

Blakemore, Robert J. & Lee, Seunghan, 2013, Survey of Busan Oligochaeta earthworms supported by DNA barcodes, Journal of Species Research 2 (2), pp. 127-144 : 134-135

11. Eisenia japonica vaga Blakemore sub-sp. n.

( Fig. 5 ).

Material. NIBR-IV0000261292 (DNA H5) H, holotype, a mature specimen collected 26 th April , from Jungang Park under (Japanese?) sakura cherry trees. IV0000250 889 (DNA WO20) P, paratype, an undissected mature specimen collected 5 th April , 2012 by RJB from near Hagae Bridge, Young River central South Korea; (a second sympatric specimen from there, IV0000250890, not tested genetically, may be similar) .

Etymology. Latin for “wandering” from its distribution that may also include New Zealand.

Description. Grey unpigmented in alcohol with white clitellum and dark dorsal vessel visible. Length 58 mm. Segments 120. First dorsal pore 4/5. Clitellum ½ 23-31. TP distinctively raised on 27 and 29. Setae ab on 11, 17 and 18 faintly marked; ab on 25 and 26 clearly tumid. Spermathecal pores in 9/10/ 11 in c lines. Holandric: testes iridescent in 10 and 11; seminal vesicles in 9-12, the latter elongate. Last hearts in 11. Calciferous glands in 11 and 12. Intestine from 15. Gizzard in 17-18. Typhlosole large T-shaped from about 19 onwards. Nephridial bladders sausage-shaped. Gut contains mainly mineral soil (i.e., a topsoil species that is at least partly geophageous).

Remarks. Superficial agreement supported by its DNA data shows this to be part of the Eisenia japonica Michaelsen, 1892 species-complex. It is not clear which part is closest, however it is remarkably similar to a New Zealand specimen described by Blakemore (2012c: fig. 3, 2013a: 40, 45). The DNA data is unequivocal that the Busan specimen objectively represents an as yet unknown taxon, and ditto sample WO20 having 99% agreement ( Fig. 1 and Appendix). The current specimen sequence is only 92-93% similar to GenBank specimens unidentifi- ed as “ Lumbricidae sp.” (AB607078) or as Eisenia japonica (AB542698) from Japan. And it is just 82-83% similar to the author’s Eisenia japonica japonica (Michaelsen, 1892) topotype from Enoshima, Japan or to E. j. hiramoto Blakemore, 2012 from near Yokohama. Such genetic dissimilarity (~20%) is normally associated with separate species/genera or even separate families (e.g. see sample H2 megaBLAST results in Appendix).

The scant difference from previous descriptions (e.g. by Kobayashi, 1941; Gates, 1975; Blakemore and Grygier, 2011; Blakemore, 2012c) of E. japonica are perhaps the tumid setae ab only on 25 and 26 (cf. on 22 and 26 in a syntype - Fig. 5 ), and the TP on 27 and 29 maybe less triangular. Differences from E. japonica minuta ( Oishi, 1934) supposedly from Morioka and Asamushi, Japan that is, however, more usually combined under the nominal taxon, are that the TP are not so round and the size is slightly more than 24-55 mm as allowed for by Oishi (1934) and later by Kobayashi (1941: 153) and Easton (1981, tab. 2).

Kobayashi (1941) had specimens from “Keiki-dô” identified as A. japonica minuta Oishi, 1934 - they also had setae ab of 25 and 26 on oval papillae - although it is now certain neither that this complies with the Japanese originals nor that his identification is correct in light of the new information presented here. Moreover, that the specimen providing DNA sample WO19 ( Fig. 1 and Appendix) represents E. japonica gigantica ( Oishi, 1934) originally from Tomakomai, Japan reported from “Kwaizan” in Chúngchóng-bukto, South Korea by Kobayashi (1941: 152) is also unclear. Neither minuta nor gigantica have since been found and reported sufficiently for comparison by subsequent Japanese workers.

Eisenia japonica vaga is a molecular taxon objectively defined on its definitive DNA.

Figures

Fig. 5. A. Eisenia japonica vaga sub-sp. n. Busan holotype (H, DNA H5). B. Eisenia j. japonica (Michaelsen, 1892) Berlin syntype Nr. 2117 (as anticipated, DNA was not extractable from this older material), author’s sketch after Blakemore and Grygier (2011, fig. 2) that compares to Hamburg syntypes V119-V121 (see Blakemore and Grygier, 2011, fig. 3).

Fig. 1. MEGA5 Maximum Likelihood phylogram of DNA code results for Busan specimens compared to similar taxa. Solid squares (■) are Busan samples; open circles (○) are unconfirmed GenBank names (from China, Korea or Japan); closed circles(●) are from the author’s Japanese studies.(Sample codes and provisional or new species names are explained in the Appendix legend).