Jeju-do earthworms (Oligochaeta: Megadrilacea) - Quelpart Island revisited
Author
Blakemore, Robert J.
text
Journal of Species Research
2013
2013-02-28
2
1
15
54
http://dx.doi.org/10.12651/jsr.2013.2.1.015
journal article
10.12651/JSR.2013.2.1.015
2713-8615
13136911
Amynthas gracilis gracilis
(Kinberg, 1867)
[
Fig. 8A
]
Material examined.
IV000251208 from Cheonji-yeon Falls, 13
th
June, 2012. Mature specimen sketched and dissected providing DNA sample (w63).
Description.
(
Jeju
specimen in summary). Genital marking discs median to male pores, postsetally with small stalked glands corresponding internally. Spermathecal pores in 5/6/7/8, first dorsal pore in 11/12. Septa 7/8 present to base of gizzard, 8/9 absent. Spermathecae in 6-8, with saccular ampulla on muscular duct with thin diverticula stalk having small, spherical bulb. Holandric. Prostates glands well developed in 18. Intestinal caeca incis- ed ventrally. Typhlosole absent.
Remarks.
The current specimen complies morphologically with current concepts of “
A. gracilis
” (e.g., by
Gates, 1972
;
Sims & Gerard, 1999
;
Blakemore, 2010b
), another cosmopolitan species from tropical and warm temperate localities.
Blakemore (2010b)
noted that
Amynthas bouchei
,
A. omodeoi
and
A. edwardsi
all by Zhao & Qiu in Zhao
et al.,
2009 from
Hainan
,
China
in the same
“
hawayanus
species-group”, are possible syns. nov. of
A. gracilis
.
Sims & Easton (1972: 176
, 214) remarked that
gracilis
was the type-species of the monotypic genus
Nitocris
Kinberg, 1867
, a pre-occupied name, and made it representative of their
“
hawayanus
species-group” while noting that the precise identity of the type-series could not be established as the specimens are immature.
Fig. 7.
Amynthas corticis saeseum
sub-sp. nov. holotype showing ventral aspect; prostomium, spermathecae (those on lhs from P1), gland in 18 and caeca
in situ
with [boxed] enlargement of spermathecae from H and P1 and of male area 18rhs].
Kinberg’s original description, in full, was: “
N. gracilis
n. Lobus cephalicus longitudinem partis mediae superioris segmenti buccalis aequans; segmenta 89-91; longitudo
42-66 mm
. Rio de Janeiro, in horto botanico
.”
The current specimen complies with earlier descriptions although it lacks the GMs frequently seen in some or all of 6-8,9 near the spermathecal pores in 5/6/7/8 and in groups of up to eleven (or twelve) median to male pores and sometimes on 17 and 19 too (
Gates, 1972: 189
;
Sims & Gerard, 1999: 130
). Without reference to DNA data, this would reasonably be the first record from
Korea
. However, a potential sub-species is tentatively described below that differs from the more familiar concept of the cosmopolitan
A. gracilis
, yet its DNA - at least for the part of the COI gene - agrees 100% with the current specimen. At the same time, the only previously
A. gracilis
barcodes from
Japan
seem to indicate slight differences (Appendix). Morphology and DNA are recorded, leaving the outcome of the issue of correct identity and taxonomic relationship of either taxon flagged for future reference.