Fróðskaparrit - 01.01.2006, Page 151

STAKIR SJÓBJØLGAR (TUNICATA, ASCIDIACEA
OG SORBERACEÁ) VIÐ FØROYAR
149
ible on the ventral side. There are about 20 to 25 ir-
rcgularly disposed tentacles of 3 to 4 orders. The dor-
sal tubercle is situated in a deep depression. The
branchial sac of the large specimens has four folds;
in younger specimens the forth fold is frequently rudi-
mentary. The longitudinal bars of a 1.5 cm specimen
were counted:
Dorsal lamina 1013715915 11 124 Endostyle
Tltere is in average two stigmata betwcen the longi-
tudinal bars. The branchial sac is globular. The esoplt-
agus leads to a fairly globular stomach with 15 to 20
longitudinal folds and a small pyloric caecum. The
intestinal loop is S-shaped. Anus is lobed with about
15 fine glands. There is one gonad on each side of
the body; a long slightly sinuous tubular ovary round
the lower end of wltich are grouped 6 to 20 testicu-
lar follicles. The sperm channels join to form a sin-
gle spcrm duct. There are a small number of endo-
carps dispersed mainly dorsally. The atrial siphon is
surrounded by small filiform tentacles.
Styehi theeli (Ámbeck-Christie-Linde,
1921)
Good description: Ámbáck-Christie-Linde, 1921:18-21;
pl. 1, figs. 5-9.
i’rcvious records: None.
blOFAR station (numbcr of individuals in parentheses):
090(4).
lidOFAR arca: Southern poinl of the plateau (Fig. 26).
•IIOFAR dcpth range: 252 m.
BIOFAR temperatures: Estimated 8 °C.
^igure 21. Styela tlieeli (front Liitzen, 1967).
BIOFAR water mass: AW.
North Atlantic/Nordic Seas distribution: Faroes; Bergcn
and ITardanger Fjord, Norway; and Koster Channel,
Sweden.
General distribution: As above.
General depth range: 252 (present study) to 640 m (Ám-
beck-Christie-Linde, 1921).
Remarks: Confusion remains regarding this rare species
which resembles in some respects S. coríacea; it has
bcen recorded at only thrce localities, all within the
boreal eastern Atlantic.
Of external differences it is notable that S. theeli is
larger in size and attached by the left side of the body.
Of intemal differences the main characteristic sepa-
rating these two species is in the numbers of gonads
(one on left and two on riglit side in 5. tlieeli, and
one gonad on e(ich side in S. coríacea); also the fomt
of (bent along a sharp angle in S. theeli whilst sinu-
ously curved or L-shaped in S. coriacea) and size of
the gonads (larger in S. theeli) are different in the
two species. See Ámbáck-Christie-Linde (1922) for
a contparison between the species.
S. theeli was synonyntized with S. coríacea by Mon-
niot (1969b). In order to clarify whether Monniot is
correct, a re-examination, especially of the gonads
of these specimens is necessary. ln relation to this it
is worth mentioning that some rare specimens of S.
rustica have duplicate gonads on one side, however,
not considered as a separate species since it is con-
sidered that this is an abnormalily (Karcn Sanamyan
pers. comm.).
In the near futurc, in order to determine the status of
this species, I plan to re-examine the four specimens
that were recorded on four dead Lophelia pertusa
blocks (Jensen and Frederiksen, 1992).
Genus: Pelonaia Goodsir and
Forbes, 1841
Pelonaia corrugata Goodsir and Forbes,
1841
Goođdescription: Hartmeyer, 1923: 187-195; Van Narne,
1945; Millar, 1966: 85, fig. 57.
Previous records: The Faroes referred to as a locality
(Traustedt, 1880).
BIOFAR station: Not recorded by BIOFAR.