Fróðskaparrit - 01.01.2004, Page 291

SIPUNKULA-ORMAR í FØROYSKUM SJÓØKI
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Identiíkation keys to Families, Genera and Species of Sipuncula
Key to Families of Class Sipunculidea
1. A single nephridium present
Two nephridia present
Key to Golfingiidae Genera
1. Four introvert retractor muscles
Two introvert retractor muscles
Key to Nepliasoma Species
1. Hooks absent. trunk rugose with transverse grooves in the thick body wall
Hooks present, trunk smooth without transverse grooves
2. Hooks are large and arranged spirally; digitiform tentacles fully developed
Hooks small and not spirally arranged, tentacles weakly developed,
reduced to small lobes.
3. Trunk is cylindrical, flask shaped, opaque, with short introvert,
trunk width usually more than 1/10 the length
Trunk long and very slender, transparent and threadlike with long introvert,
trunk width usually Iess than 1/10 the length of trunk
Key to Onchnesoma species:
1. Trunk covered with prominent backward directed protrusions, eight tentacles
Trunk flat without spherical protrusions or scales; tentacles absent
Key to Phascolion species
1. Dorsal and ventral retractors have equal width; holdfast spherical
and lacks hardened borders; hooks broad, strongly recurved
Ventral retractor much thinner than the dorsal retractor, holdfast usually
V-shaped with dark hardened border, hooks sharp and claw like, not recurved
Conclusion
In early investigations in the defined area
by Wesenberg-Lund (1928, 1930), only
two species of sipunculans (Ph. Strombus
and N. minutum) were found. Recent inves-
tigations (Bruntse and Tendal, 2001; Nør-
revang, 1990) added two more to the list
(On. steenstrupii and On. squamatum). In
the present work, we collecled more than
5,000 specimens from rnore than 254 rep-
resentative stations.
Analysis of the material showed six spe-
cies of Sipuncula recorded for the first time
from this area. The dominant species were
Nephasoma minutum (119 stations), Phas-
596, 689, 692, 728, 780, 1506 (total 13 stations, 22
specimens), fig. 6.
Temperature: from -0.1 - 8.6 °C. Salinity: 34.92-
35.20%„.
Depth range: 351-732 m.
Bottom type: silty sand and gravel.
General distribution: Atlantic-boreal eurybathic species.
Depth range: 25-2700m.
Atlantic distribution: from Iceland to Azores Isles,
coast of Norway, Trondheim, Bergenfjord, Swedish
coast, Kattegat, Skagenak, Mid-Atlantic Ridge, Bay
of Biscay, Azores Isles; Mediterranean: Alboran Sea,
Spanish waters, Adriatic Sea.
Phascolionidae
Golfingiidae
Golfmgia vulgaris
Nephasoma
N. eremita
N. abyssorum
N. minutum
N. lilljeborgi
On. squamatum
On. steenstrupii.
Ph. tuberculosum
Ph. strombus