Fróðskaparrit - 01.01.2004, Blaðsíða 288

286
MARINE WORMS OF THE PHYLUM SIPUNCULA IN FAROESE WATERS
common cosmopolitan name (N. minutum) only on
the basis of hermaphroditic specimens found in the
population that inhabits the north-eastern Atlantic.
Secondly, cases of hermaphroditism were noted among
other species of sipunculids (Harms, 1921) and also
nereid polychaetes (Smith, 1958). Thirdly, there are
no significant morphological differences between the
hermaphroditic populations of N. minutum, described
by Keferstein (1862) and N. diaphanes described by
Gerould (1913). It is incorrect to regard the differing
vertical distribution of these two species of the genus
Nephasoma used by Cutler (1994) as an important
criterion for the identification of these species.
As a result, N. diaphanes was considered as an junior
synonym of N. minutum. .It is appropriate to quote Peter
Gibbs’(1975) opinion: “The morphologically similar
specimens now regarded as a single species have two
distinct forms, a dioecious form found chiefly in deep
water, and a hermaphroditic form found on the shore and
in shallow water around Europe and Scandinavia”.
Class SIPUNCULIFORMES
Order GOLFINGIIFORMES
Family PHASCOLIONIDAE
Genus Onchnesoma Koren & Danielssen,
1875.
Onchnesoma squamatum squamatum
(Koren & Danielssen, 1875)
Synonyms: Phascolosoma squamatum Koren &
Danielssen (1875:129); Phascolion squamatum Theel
(1905:96).
Good description: Theel (1905: 96-98, pl. 11, ftgs. 153-
156; pl. 13, figs. 183-184, pl. 15, fig. 214-215).
Previous records: Bruntse andTendal (2001).
BIOFAR stations: 32, 33, 61, 63, 64, 65, 68, 158, 483,
518, 716, 767 (12 stations and 105 specimens in total),
fig. 4.
Temperature: 2.0-8.60 °C; Salinity: 35.00-35.20%c.
Depth range: 292-405 m.
Bottom type: silty sand, clayed sand.
■ Phascolion strombus
■ ■ ■ l \ f'
Fig. 5. Records of Phascolion strombus (Montagu, 1804)