Fróðskaparrit - 01.01.2004, Side 298

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CERIANTHARIA (CNIDARIA: ANTHOZOA) FROM THE FAROEISLANDS
Carlgren, 1912, Jensen, 1992).
Diagnosis (according to Carlgren, 1912; Molodtsova,
2001); medium-sized species with up to 40 marginal
tentacles and about the same number of labial tentacles.
Marginal tentacles are arranged in at least 2 cycles, set
very close together. Labial tentacles are in 4 cycles. A
directive labial tentacle is present. Siphonoglyph narrow,
hyposulcus distinct, but small. Protomesenteries 2 and
fertile metamesenteries (M- and m-) reach to the aboral
pole of the gastral cavity and consist of three regions:
ciliated tract, cnidoglandular tract and craspedion.
Protomesenteries 3 are about 1/3 of the gastral cavity
and consist of a rather short ciliated tract region and well-
developed cnidoglandular tract. Sterile metamesenteries
(B- and b-) have the same structure as protomesenteries
3 and differ in length from each other in the same quartet
of metamesenteries. In the aboral end of the ciliated
tract region of all mesenteries, but directives, there is a
short single craspedoneme, which sometimes could be
masked by the dense cnidoglandular plexus.
Family BOTRUCNIDIFERIDAE
Genus Botrucnidifer Carlgren, 1912
Botrucnidifer norvegicus Carlgren, 1912
(Fig.l, Fig. 2. c - d)
Good description: Carlgren (1912: 30-34).
Previous records: None.
BIOFAR stations: 532; 783 (den Hartog: personal
communication).
Area: Faroe-Shetland Channel.
Depth range: 260-396 m.
Temperature: 6.80 "C.
Atlantic distribution: Norwegian Sea, Trondheim
Fjord.
Atlantic depth range: 50-400 m (Carlgren, 1912, 1931).
Remarks: all specimens of this species were found
among colonies of ahermatipic corals and gorgonians
(Carlgren, 1912).
Suborder PENICILLARIA
Family ARACHNACTIDAE
Genus Arachnactis M. Sars, 1946
Araclinactis albida M. Sars, 1846 (fig.l,
fig. 2 e)
Synonyms: A. Lo Biancoi van Beneden (1923).
Good description: Carlgren (1906); van Beneden
(1923).
Previous records: (Sars, 1846; Vanhðffen, 1895;
Carlgren, 1906; Leloup, 1942, 1954).
BIOFAR stations: None.
Area: south and south-west of the Faroe Islands, Faroe-
Shetland Channel, Wyville-Thompson Ridge.
Depth range: 0-100 m.
Temperature: not known.
Atlantic distribution: Norwegian Sea, North Sea, Irish
Sea, English Channel, Mediterranean Sea (Carlgren,
1906; Leloup, 1929, 1931, 1960).
Atlantic depth range: pelagic: 0-1000 m.
Remarks: planktonic larvae, bottom stáge is unknown.
Conclusion
Two species of benthic cerianthids were
recorded from the BIOFAR samples: Ceri-
anthus vogti Danielssen, 1890 and Botruc-
nidifer norvegicus Carlgren, 1912. The
former had already been recorded from
the Faroe Islands (Carlgren, 1942), but the
later species was recorded for the fírst time
from the Faroe Islands. This was also the
first time it had been recorded outside of
the Trondheim Fjord (Norway). Probably
this dwarf cerianthid is distributed in the
North Atlantic more widely than previously
thought. Remarkably, B. norvegicus was al-
ways found in colonies of ahermatipic scle-
ractinians and gorgonians (Carlgren, 1912;
1931). Further investigations of this species
are needed to determine if B. norvegicus is
an obligate commensal of deep sea corals.
Cerianthus vogti Danielssen, 1890 is
widely distributed in the Northern Atlantic
at a depth of 600-2800 m. Apparently, the
vast majority of cerianthids found at these
depths in the Norwegian Sea, around the
Faroe Islands and off Iceland belong to this
species. However we cannot exclude the
possibility of the discovery of new deep sea
species in the above-referenced area men-
tioned area.