1063-0740/02/2806- $27.00 © 2002
Russian Journal of Marine Biology, Vol. 28, No. 6, 2002, pp. 365–370.
Original Russian Text Copyright © 2002 by Biologiya Morya, Morozov, Adrianov.
The sipunculans are a relatively small group of
exclusively marine coelomic worms comprising,
according to different estimates, from 250 [10, 21] to
350  species. These benthic animals are widely dis-
tributed in the oceans of the world. In bottom commu-
nities, they occupy very different habitats and occur on
rocky grounds, among the rhizomes of seagrasses and
rhizoids of algae, in mussel communities, and in coral
reefs, where they make burrows [3, 10, 28]. In some
communities, sipunculans may show great population
density and high biomass, up to several hundreds of
specimens and several kilograms per square meter .
The size of sipunculans ranges from several milli-
meters (interstitial forms) to several tens of centime-
ters. In recent decades, due to their large sizes, relative
availability, and ease of maintenance in an aquarium,
sipunculans have become favorite objects for biochem-
ical and physiological investigations.
Despite the availability and wide distribution range
of sipunculans, the taxonomy of this group remains
obscure. Different authors often present contradictory
information on many species [3, 10, 39].
The fauna of sipunculans in southern Primorye is
very poorly studied. Certain faunistic observations
have been reported only for some southern areas of
Peter the Great Bay (Pos’eta Bay) [1, 3, 4]. No faunistic
studies of this group have been performed so far in the
northern part of Peter the Great Bay. Only two taxo-
nomical papers by Popkov are available [5, 6], and,
moreover, later studies have cast well-founded doubts
upon the validity of species described therein .
The present work is the ﬁrst attempt to study the
fauna of sipinculans in Vostok Bay, Sea of Japan.
MATERIALS AND METHODS
The materials for these studies were collected dur-
ing three ﬁeld seasons of 1997–1999, in Vostok Bay,
the Sea of Japan, at the Vostok Marine Biological Sta-
tion of the Institute of Marine Biology, from a depth of
2–6 m, from clusters of
Modiolus modiolus kurilensis
, the rhizomes of
, in sandy areas in between boulders (
Immediately prior to dissection, the sipunculans
were narcotized with a 10% solution of magnesium sul-
) or magnesium chloride (MgCl
entire loss of response to the stimulus of a dissection
needle. Then, the area behind the pharynx was clamped
with forceps to prevent the invagination of the introvert.
The head regions of the animals were then cut off and
ﬁxed, together with the trunk regions for systematic
collection and preliminary identiﬁcation or separately
for further morphological and ultrastructural studies.
The animals were ﬁxed with 8% formalin prepared
with seawater with addition of some alkali and fresh
water to level the ﬁxative osmomolarity with that inside
the body of the animal.
Species identiﬁcation was performed on dissected
animals, using the entire set of anatomical and external
morphological characteristics. For this purpose, we
also prepared glycerin preparations of epidermal
organs (scalids of the introvert and trunk papillae). The
preparations were examined with a Reichert Polyvar
microscope using Nomarski optics. We also prepared
some permanent preparations of the most typical papil-
lae and scalids, which, after the transition via Seinhorst
solution, were embedded into Hoyer’s solution and
then deposited in our systematic collection.
Fauna of Sipunculans (Sipuncula) of Vostok Bay, Sea of Japan
T. B. Morozov
and A. V. Adrianov
Far East State University, Vladivostok, 690000 Russia
Institute of Marine Biology, Far East Division, Russian Academy of Sciences, Vladivostok, 690041 Russia
Received July 10, 2002
—Fauna and systematics of sipunculans inhabiting Vostok Bay, Sea of Japan, are discussed. A revision
of the local species of sipunculans is performed for the ﬁrst time. On the basis of study of outer and inner mor-
phology, some species are reduced to synonyms. Extended diagnoses are proposed for all registered species.
An identiﬁcation key is presented for the sipunculans of Vostok Bay.
systematics, sipunculans, Sipuncula, Golﬁngiidae, Phascolosomatidae, Themistidae,