1063-0740/03/2902- $25.00 © 2003
Russian Journal of Marine Biology, Vol. 29, No. 2, 2003, pp. 120–122.
Original Russian Text Copyright © 2003 by Biologiya Morya, Orlova, Selina, Shevchenko.
It is known that the lifecycle of more than 80 extant
marine dinoﬂagellate species includes the dormancy
stage presented by cysts . Examining dinoﬂagellate
cysts is important in terms of studying the ecology and
biogeography of these algae . The motile stage may
be relatively short, and the identiﬁcation of some, espe-
cially naked, species presents a difﬁculty and becomes
absolutely impossible in the case of ﬁxed cells. Hence,
studying cysts from a certain water area helps to ﬁnd
species that were not revealed in plankton surveys 
and thus to extend ﬂoristic lists and to specify in greater
detail the biogeography of a species.
Cysts typical of some naked dinoﬂagellate spe-
cies—members of Gymnodiniaceae—were found in
samples of the surface sediment from Peter the Great
Bay (Sea of Japan). The germination of cysts provided
a clone containing motile vegetative cells identiﬁed as
Freudenthal et Lee.
is known from plankton collections
from New York Bay (Northern Atlantic) . It is wide-
spread in neritic and estuary waters of the tropico-
boreal zone . It was reported to cause water bloom-
ing and red tides off the Paciﬁc coast of Japan and the
coast of Ecuador [7, 13].
gotes) were ﬁrst found in, and described from, the sur-
face sediment from the Inner Sea of Japan . Later on,
they were found in the sediment off the Paciﬁc coasts of
Japan where this kind of cysts is dominant. In the vicin-
ity of the port of Yokogama, it dominates, accounting
for over 53% of the total number of dinoﬂagellate cysts
. To date,
cysts and motile cells have
not been reported for the seas of Russia.
The present study adds to the description of the mor-
cysts and motile cells and cor-
rects and extends the present data on the ecology and
geographical distribution of the species.
MATERIALS AND METHODS
The material was obtained from the surface sedi-
ment at 25 stations in different parts of Peter the Great
Bay (Sea of Japan) June–October 1999. Samples were
collected by SCUBA divers into glass or metal tubes
45 mm in diameter. The upper 0- to 2-cm portion of a
sample was used in analysis. It was then sonicated
using a Branson 250 ultrasound soniﬁer and screened in
series through Nitex capron screens sized to 80 and
m to obtain a 20- to 80-
m cyst fraction, contain-
ing living dinoﬂagellate cysts. To obtain a culture, sep-
arate cysts were collected using microcapillaries under
microscopic control and placed into containers with the
f/2 medium . The containers were kept in an incuba-
tor at 15
C under a schedule of 12 h light : 12 h dark.
G. instriatum Freudenthal et Lee, 1963: 182–189,
(see Fig. 1a–1c). The cysts are
pear-shaped, concave in lateral view, 51–55
m wide. The wall is thick, unstructured,
surrounded with a thick mucous layer with agglutinous
detritus particles. The body wall of some cysts has
paracingulum (see Fig. 1c). A living cyst contains
numerous colorless and orange to brown granules, most
of which are accumulated closer to the center of the cyst
(see Fig. 1a). The archeopyle can be observed on the
top of the apex of empty cysts as a round hole through
which excystment occurs.
cysts were found in the
samples from 16 stations in Amurskii, Gaidamak, and
Vostok bays and Nakhodka, Pemzovaya, Novgorod-
skaya, and Minonosok bights. Their density in sedi-
ment was not over 100 spec/cm
The Morphology of Cysts and Motile Cells of
(Dinophyta), a Species New to the Seas of Russia
T. Yu. Orlova, M. S. Selina, and O. G. Shevchenko
Institute of Marine Biology, Far East Division Russian, Academy of Sciences, Vladivostok, 690041 Russia
e-mail: email@example.com; tatiana_orlova@ mail.primorye.ru
Received October 11, 2002
—The germination of dinoﬂagellate cysts isolated from the surface sediment from Peter the Great Bay
(Sea of Japan) provided motile cells of
. This is the ﬁrst report on this species for the seas
of Russia. The morphology of both collected and germinated cysts and motile cells is described, and data on
the ecology and distribution of the species are provided.
, dinoﬂagellates, cysts, Sea of Japan.