Fróðskaparrit - 01.01.2006, Blaðsíða 150

148
SOLITARY ASCIDIANS (TUNICATA, ASCIDIACEA
AND SORBERACEA) OF THE FAROES
Figure 20. BIOFAR records of Styela rustica • and S. similis •
General depth range: From shallow water to more than
400 m (Millar, 1966).
Remarks: The specimens found off the Kola Peninsula
in the Arctic and the Gulf of Saint Lawrcnce between
Pictou and Cape Bear in the boreal western Atlantic
have a more rounded dorso-ventrally flattened body
form contrary to the elongated cylindrical shape in
specimens from otherareas (Árnbáck-Christie-Linde,
1922; Van Name, 1912). The reasons for these ex-
ternal variations might be ascribed variations in the
physical environment and thereby exclusively phe-
notypic, or thcy may be caused by the same rcason
as mentioned forY. coreacea (see above), and thereby
without genetic signiftcance. Molecular analyses
would state whether these specimens are different ge-
netically from the typical fonn of S. rustica.
Styela similis Monniot, 1970
Good description: Monniot, 1969a: 1143; fig. 4 a-d + pl.
I.
Previous records: None.
BIOFAR station (number of individuals in parentheses):
476(1) (Fig. 20).
BIOFAR area: West of Munkagrunninum (Fig. 20).
BIOFAR depth range: 252 m.
BIOFAR temperatures: Estimated to 7.00 °C.
BIOFAR watcr mass: AW.
North Atlantic/Nordic Seas distribution: Faroes , west of
Ireland, and Bay of Biscay.
General distribution: Also recorded in Angola (33°22'S;
02°40'E).
General dcpth range: 250 to 4600 m (Monniot and Mon-
niot, 1985).
Remarks: According to Klitgaard (1995), a single juve-
nile specimen, identified by Claude Monniot, was
recorded on the sponge Isops phlegraei Sollas, 1880.
Taxonomic remarks: 1 havc not examined the specimen.
A translation of Monniot’s (1969a) dcscription is as
follows: Small specimens of S. similis are completely
covered with foraminiferans, larger specimens m
lesser extent. Up to 1.5 cm long; siphons are slightly
projecting. The tunic is aiways delicate; it is suffi-
ciently resistant on the dorsal side, whilst the ventral
part that fixes the animal to the substrate is invisible
and extremely delicate. The mantle contains mus-
cles only on the dorsal side; also the mantle is invis-