Cladocera (Crustacea: Branchiopoda) of the south-east of the Korean Peninsula, with twenty new records for Korea *
Author
Kotov, Alexey A.
Author
Jeong, Hyun Gi
Author
Lee, Wonchoel
text
Zootaxa
2012
3368
50
90
journal article
10.5281/zenodo.214313
f69535e8-6850-402e-992d-09316696daf4
1175-5326
214313
13.
Disparalona ikarus
Kotov & Sinev, 2011
Figs 18–19
Synonymy.
Disparalona ikarus
Kotov & Sinev, 2011
, p. 272–276, Figs 1–2.
?
Disparalona rostrata
(Koch)
in
Kim & Yoon 1987
, p. 200–202,
Fig. 11
c–e;
Yoon 2010
, p. 134–135, fig. 73.
Type
locality.
“Mouth of the Tom River (51°02.137ʹN, 127°53.370ʹE)" (Kotov & Sinev 2011), Amur Area,
Russia
.
Localities in
Korea
.
2, 6a (see Fig. 1 and
Table 1
).
FIGURE 18.
Disparalona ikarus
Kotov & Sinev, 2011
, adult parthenogenetic female from Bak Sil Ji 1, locality 6a: A–C, lateral, ventral and dorsal view; D–E, anterior view of two different individuals; F, dorsal head pores; G, labrum; H, postero-ventral valve portion, inner view. Scale bars: 0.1 mm.
Parthenogenetic female.
Body moderately elongated for the genus, postero-dorsal angle distinct, lacking any denticles, posterior margin straight, postero-ventral angle widely rounded (
Fig. 18
A, 19D). A lateral wing-like projection on each side of brood pouch (
Fig. 18
B–C), in anterior view from rounded-triangular to acute (
Fig 18
D–E). Sculpture of low longitudinal folds well-expressed in dorsal portion, visible as longitudinal lines in lateral view. Compound eye 2 times larger than ocellus. Dorsal head pores typical for the genus (
Fig. 18
F). Labral keel relatively narrow, with widely rounded apex (
Fig. 18
G). In posterior portion of ventral margin, setae located slightly submarginally, no setules between them; a row setules submarginally at posterior margin (
Fig. 18
H). Postabdomen elongated in both adults in juveniles (
Fig. 19
A, E), fluently narrowing distally, its length about 3.5 width. Preanal margin straight, preanal angle distinct, anal margin convex, postanal margin regularly curved to the base of postabdominal claw; dorso-distal angle and distal margin not expressed. About 7–8 long and thin singular postanal teeth, rows of setules on anal margin; setules in lateral series short. Postabdominal claw somewhat curved, as long as preanal margin, with a very short basal spine and an additional setule. Antenna I (
Fig. 19
B) and II typical for genus. Limb I with ODL bearing a single seta, IDL with two long setae setulated distally and a short seta with pointed tip (
Fig. 19
C). Size in our material 0.35–0.48 mm.
FIGURE 19.
Disparalona ikarus
Kotov & Sinev, 2011
, adult (A–C) and juvenile (D–E) parthenogenetic female from Bak Sil Ji 1, locality 6a: A, postabdomen; B, antenna I; C, distal portion of limb I; D, juvenile, lateral view; E, its postabdomen. Scale bars: 0.1 mm.
Notes.
This taxon was known from a single locality in the Amur basin. Now it is obvious that it is more widely distributed in the Far East, although the most common species there is
D. cf. hamata
(Birge, 1879)
(
Fig. 20
A–D).
Disparalona ikarus
differs from the latter in: (1) presence of lateral “wings”; (2) absent striae between reticulation lines; (3) weak dorso-distal angle and distal margin of postabdomen; (4) short basal spines on postabdominal claw; (5) absence of a strong hook-like seta on IDL. Although
Kim & Yoon (1987)
and
Yoon (2010)
illustrated their "
Disparalona rostrata
" only in lateral view, we can conclude that, most probably, they were dealing with
D. ikarus
,
keeping in mind differences between these two species in shape and armature of the postabdomen.