Nonmarine Ostracoda (Crustacea) from Jeju Island, South Korea, including descriptions of two new species
Author
Smith, Robin James
Lake Biwa Museum, Kusatsu, Shiga, Japan;
Author
Lee, Jimin
Marine Ecosystem Research Division, Korea Institute of Ocean Science and Technology, Ansan, Korea;
Author
Chang, Cheon Young
Department of Biological Science, College of Natural Sciences, Daegu University, Gyeongsan, Korea
text
Journal of Natural History
2014
2014-06-30
49
1
37
76
journal article
21101
10.1080/00222933.2014.946110
09639ec6-6fbb-42e3-aab5-9a3ed49c09cd
1464-5262
4002512
Genus
Bradleytriebella
Savatenalinton and Martens, 2009a
Bradleytriebella tuberculata
(
Hartmann, 1964
)
(
Figure 2G–J
)
Strandesia tuberculata
Hartmann, 1964
Strandesia decorata
(
Sars, 1903
)
–
Okubo 1990b
,
2004
. Synonymy herein.
Bradleystrandesia tuberculata
(
Hartmann, 1964
)
nov. comb
.
Savatenalinton and
Martens 2009b
Bradleytriebella tuberculata
(
Hartmann, 1964
)
nov. comb.
Savatenalinton and
Martens 2009a
Remarks
The Korean specimens closely match the redescription provided by
Savatenalinton and Martens (2009a)
, with the exception that the two small sub-marginal tubercles at approximately mid-height on the anterior part of the carapace (one on each valve) are very weakly developed or absent in the Korean material. In one specimen, there are very small tubercles on the carapace seen in dorsal view (marked with triangles on
Figure 2H
), which correspond to the areas where tubercules are present in specimens from other areas. Within the superfamily
Cypridoidea
, some species have ornamentation present in some specimens while it is lacking in others. For example,
Ilyocypris gibba
(
Ramdohr, 1808
)
,
Ilyocypris decipiens
Masi, 1905
,
Prioncypris zenkeri
(Chyzer and Toth in
Chyzer, 1858
)
,
Heterocypris incongruens
(
Ramdohr, 1808
)
, and
Heterocypris salina
(
Brady, 1868
)
typically have tubercles or denticles on the carapace, but such ornamentation can be lacking in some specimens/populations (
Meisch 2000
). In the superfamily
Cytheroidea
, the presence or absence of tubercles of
Cyprideis torosa
is ecophenotypically induced (e.g.
Keyser 2005
), although it is not known what causes differences in surface ornamentation in the
Cypridoidea
. As the appendages and other carapace features of the Korean specimens are identical to the redescription of
B. tuberculata
from
Thailand
, we conclude that the Korean specimens represent a form of
B. tuberculata
with very weakly developed or absent tubercules.
In
Japan
, both
Strandesia tuberculata
and
Strandesia decorata
(
Sars, 1903
)
have been reported (
Okubo 1990b
), but later the Japanese specimens were considered to all be
S. decorata
(
Okubo, 2004
)
. However,
S. decorata
has a smooth carapace (
Sars 1903
;
Savatenalinton and Martens 2010
), whereas the Japanese specimens are clearly striated. We consider that the Japanese and Korean specimens are conspecific, and specimens with weak or no tubercles attributed to
S. decorata
by
Okubo (1990b
,
2000
,
2004
) are
B. tuberculata
. The Thai specimens figured by
Savatenalinton and Martens (2009a)
also appear to have two weakly developed posterior tubercules in addition to the two anterior tubercles, similar to
Strandesia spinulosa
Bronshtein in
Akatova, 1958
. Further investigation is required to determine whether these two species are synonyms.
Bradleytriebella tuberculata
is known from
India
(
Hartmann 1964
as
S. tuberculata
),
Thailand
(
Savatenalinton and Martens 2009a
),
Japan
(
Okubo 1990b
as
S. tuberculata
and
S. decorata
;
Okubo 2000
as
S. tuberculata
and
S. decorata
;
Okubo 2004
as
S. decorata
), and
Taiwan
(
Yu et al. 2009
, as
Bradleystrandesia tuberculata
, citing grey literature). From
Japan
and
Thailand
it is known from rice fields, whereas the Korean specimens were recovered from a streamside seep (locality 17) and an irrigation pond (locality 26).