Earthworms from Matsu, Taiwan with descriptions of new species of the genera Amynthas (Oligochaeta: Megascolecidae) and Drawida (Oligochaeta: Moniligastridae)
Author
Shen, Huei-Ping
Author
Chang, Chih-Han
Author
Chih, Wen-Jay
text
Zootaxa
2015
3973
3
425
450
journal article
40179
10.11646/zootaxa.3973.3.2
bd134967-6da8-4ef1-a3dd-5733437017d9
1175-5326
232280
10FA49C7-E806-4B89-B9BF-21C1F3E9EC03
Drawida beiganica
Shen & Chang
,
sp. nov.
(
Figure 4
)
Holotype
:
Clitellate (mature) specimen (
86 mm
in total length, dissected), Beigan, along the road between Chinbi Village and Bishan Lookout,
26°13'22.7''N
,
119°59'16.7''E
,
210 m
asl,
26 June 2012
, H.P. Chen & W.J. Chih (TESRI-O-H-45; MTS 141).
Paratypes
:
2 clitellates (one dissected, the other amputated), Nangan, Shengtien Reservoir,
26°09'13.9''N
,
119°54'59.7''E
,
70 m
asl,
28 May 2012
, H.P. Chen & T.L. Ai (TESRI-O-P-40).
Other material.
24 specimens
altogether.
1 specimen
(amputated), Beigan, from a roadside ditch at Chinbi Village,
26°13'32.0''N
,
119°59'03.3''E
,
11 m
asl,
29 May 2012
, H.P. Chen & T.L. Ai (TESRI-O-
2012-39
-13; MTS 30);
3 specimens
, Beigan, in front of Matsu Broadcasting Station,
26°13'16.7''N
,
119°58'47.5''E
,
205 m
asl,
29 May 2012
, H.P. Chen & T.L. Ai (TESRI-O-
2012-43
-6; MTS 40);
12 specimens
, Nangan, near Nangan Airport,
26°09'09.2''N
,
119°57'17.1''E
,
58 m
asl,
31 May 2012
, H.P. Chen & T.L. Ai (TESRI-O-
2012-55
-4);
1 specimen
, Nangan, Stronghold No. 12,
26°10'02.5''N
,
119°57'06.2''E
,
59 m
asl,
25 June 2012
, H.P. Chen & W.J. Chih (TESRI-O-
2012-60
-9; MTS 91);
2 specimens
, Beigan, Tangchi Village, near a trash treatment field,
26°13'59.9''N
,
120°00'17.4''E
,
64 m
asl,
26 June 2012
, H.P. Chen & W.J. Chih (TESRI-O-
2012-61
-11; MTS 99);
5 specimens
, Beigan, along the road between Chinbi Village and Bishan Lookout,
26°13'22.7''N
,
119°59'16.7''E
,
210 m
asl,
26 June 2012
, H.P. Chen & W.J. Chih (TESRI-O-
2012-63
-13; MTS 109, 142).
Diagnosis.
Length
55–86 mm
, weight
0.31–0.69 g
, diameter
3.2–4.8 mm
. Segments numbering 120–169. Prostomium prolobous. Dorsal pores absent. Setae lumbricine, short and closely paired. Clitellum in X–XIII, paler, swollen. Spermathecal pores one pair in 7/8. Penes usually wholly concealed or slightly visible externally when in retracted condition, and long, conical, stouter at base and pointed forward when entirely protruded, with a slit-like male pore situated at its free end. Secondary male aperture transverse slits in 10/11. Female pores minute, hardly visible, one pair on anterior-most border of XII, each pore in line with seta b. Genital markings absent. Gizzards three in XIII–XV. Testis sacs one pair, large, each suspended on septum 9/10. Sperm duct long, in form of a large mass of white, twisted fine tubes. Male atrium S- or boomerang-shaped, its proximal end in connection with coelomic surface of penis pouch. Spermathecae one pair. Ampulla large, oval-shaped, with slender, coiled duct. Spermathecal atrium oval, sac- or thumb-like. Accessory glands absent.
Description.
Length
55–86 mm
(amputated specimens not included), weight
0.31–0.69 g
, diameter
3.2–4.8 mm
. Segments numbering 120–169. Prostomium prolobous. Dorsal pores absent. Setae lumbricine (eight setae per segment), short and closely paired, ab = cd, aa = 0.8 bc, aa> 6 ab, dd greater than 0.5 body circumference. Clitellum in X–XIII, paler, swollen. Spermathecal pores one pair in 7/8, each pore medial to seta c, slit-like, edge slightly wrinkled. Penes usually wholly concealed or slightly visible externally when in retracted condition, and long, conical, stouter at base and pointed forward when entirely protruded, with a slit-like male pore situated at its free end, the entire length about two segments (
Fig. 4
A). Secondary male aperture transverse slits between bc in 10/ 11, with whiter margin surrounded by swollen skin. Female pores minute, hardly visible, one pair on anterior-most border of XII, each pore in line with seta b. Genital markings absent. Preserved specimen grayish or pale gray, and paler or pink around clitellum.
Internal:
Septa
5/6–8/9 thick and muscular, 9/10 thin. Gizzards three in XIII–XV, round, white, muscular and shining. Hearts four pairs in VI–IX. Nephridia holoic. Testis sacs one pair, large, yellowish, elongated oval, each suspended on septum 9/10,
1.78–1.95 mm
in length and
1.65–1.75 mm
in width. Sperm duct long, in form of a large mass of white, twisted fine tubes, running in front of septum 9/10, penetrating septum into segment X and passing along dorsal surface of the male atrium (
Fig. 4
B). Male atrium white, S- or boomerang-shaped, its proximal end in connection with coelomic surface of penis pouch. Penis pouch elevated as a dome-shaped bulge when penis retracted. Ovarian chamber formed by septa
10/11 and 11/12
, meeting in front of the gizzard on dorsal side. One pair of follicular, yellowish ovisacs dorso-lateral on both sides of the digestive tract, extending posteriorly to segment XIV–XVI, broader anteriorly and narrower posteriorly, moniliform or constricted by each septum. Spermathecae one pair, ampulla anterior while spermathecal atrium posterior to septum 7/8. Ampulla large, oval-shaped,
1.25–1.38 mm
long and
1.07 mm
wide, its duct long, slender, at first straight and then passing into several coils to join the spermathecal atrium (
Fig. 4
C). Atrium oval, sac- or thumb-like,
0.65–0.8 mm
in length and about
0.4 mm
in width. Accessory glands absent.
FIGURE 4.
Drawida beiganica
sp. nov.
Holotype (TESRI-O-H-45).
A.
Ventral view of spermathecal and male pore region (one penis is shown everted and the other one is retracted) (sp, spermathecal pore; mp, male porophore).
B.
Dorsal view of right testis sac (ts), sperm duct (sd) and male atrium (ma).
C.
Dorsal view of left spermatheca (amp, ampulla; sa, spermathecal atrium). Scale bars = 1 mm.
DNA barcodes.
GenBank accession numbers
KJ782577
(MTS 141,
holotype
),
KJ782578
,
KJ782579
,
KJ782582
,
KJ782580
,
KJ782581
and
KJ782583
(MTS 30, 40, 91, 99, 109 and 142, respectively).
Etymology.
The name
beiganica
is given to this species with reference to its
type
locality in Beigan, Matsu.
Remarks.
Drawida beiganica
sp. nov.
is found on the islands of Beigan and Nangan. The shape of its penis is fairly similar to that of
Drawida beddardii
(
Rosa, 1890
)
from
Burma
. However, the penes of
D. beddardii
are much shorter with length a little more than half the segment (specimen No: 125407 of Smithsonian Institution, National Museum of Natural History identified by Gates and examined by H.P. Shen), while those of
D. beiganica
are about two segments long. Also,
D. beddardii
has large spermathecal pores (
Gates 1972
) whereas those of
D. beiganica
are small slits. Furthermore, sperm ducts are rather short and not twisted in
D. beddardii
(
Rosa 1890
;
Gates 1972
) and long, in form of a large mass of white, twisted fine tubes in
D. beiganica
.
Beddard (1895)
,
Michaelsen (1900)
,
Stephenson (1923)
and
Blakemore
et al
. (2014)
considered that
D. beddardii
is synonymous to
Drawida barwelli
(
Beddard, 1886
)
.
Gates (1929)
included
D. beddardii
in
D. barwelli
but later (1962) maintained these two species separately and stated that
barwelli
was never found in
Burma
. Also,
Easton (1984)
excluded
D. beddardii
as a synonym of
D. barwelli
. In the original brief description of
Beddard (1886)
, sperm ducts of
D. barwelli
are thin, delicate and much coiled. However, sperm ducts of
D. beddardii
are quite short and not twisted (
Rosa 1890, Fig. 12
). Obviously,
D. beddardii
is a valid species distinguishable specifically from
D. barwelli
.
Drawida tairaensis
Ohfuchi, 1938
from
Japan
often lacks genital papillae and is fairly similar to
D. beiganica
externally when penes of both species are in retracted condition. However, the penes of
D. tairaensis
are short and pointing ventro-medially when entirely protruded (
Ohfuchi 1938
). In addition, the spermathecal atrium of
D. tairaensis
is long, cylindrical and always situated in segment VII (
Ohfuchi 1938
), while that of
D. beiganica
is oval, sac- or thumb-like and located in segment VIII.
Drawida beiganica
is also similar to
Drawida eda
Blakemore, 2010
from
Japan
in body size and in having no genital markings. However,
D. eda
has inward-facing, comma-shaped penes, spermathecal ampulla on posterior face of septum 7/8, much shorter sperm ducts, and five gizzards in XIII–XVII (
Blakemore & Kupriyanova 2010
), which differ greatly from those of
D. beiganica
.