Fróðskaparrit - 01.01.2006, Side 148

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SOLITARY ASCIDIANS (TUNICATA, ASCIDIACEA
AND SORBERACEA) OF THE FAROES
Figure 17. BIOFAR records of Styela coríacea.
the Arctic and a11 thc northern boreal regions, and
common within thc Faroese EEZ.
Gencral depth range: From shallow water to at least 600
m (Millar, 1966).
Remarks: S. coriacea has two forms of extemal appear-
ance, a low dorso-ventrally compresscd form and a
tall, cylindrical form(Kjær, 1893; Árnbáck-Christie-
Linde, 1922). This variation might be an expression
of various environmental conditions, a point which
is supported by the occurrence of all intermediate
forms (Bjcrkan, 1905; 1908). Moreover, the specics
is known to be highly contractile and able to change
itsshapegreatIywhcnalive(VanName, 1912; 1945),
hence the degree of contraction varies in preserved
specimens; contraction occurs frequently regardless
how careful specimens are relaxed before preserva-
tion (Gretchcn Lambert pers. comm.).
Styela gelatinosa Traustedt, 1886
Good dcscription: Traustedt, 1886: 429; pl. 36, figs. 8-
10; pl. 38, fig. 27; Hartmeyer, 1923; pl. 1, figs. 9-11;
Millar, 1966; 67, fig. 43.
Figure 18. Styela gelatinosa (from Liitzen, 1967).
Previous records: "Fylla ” 1890: The slope of the Faroe-
Shetland Channel 924 m (61°23'N;4°49'W) (Hart-
meyer, 1923). “Michael Sars" 1902: Faroe-Iceland
Ridge 480 m (63‘,14'N;9°46 W); Faroe-Shctland
Channel 1130m(60°19'N;5°06'W)(Bjerkan, 1905)-
Sampled 1904 or earlier: Southern end of the Faroe-
Shetland Channcl 588 m (60°37'N;05°42'W)
(Michealsen, 1904 (in Hartmeycr, 1923)).