A guide to the deep-water sponges of - NMFS Scientific Publications ...

63. Hymedesmia (Stylopus) dermata Lundbeck, 1910
Description. This sponge is small, thin, and encrusting.
Oscula are not visible on the surface. Consistency
is soft. Color in life is light orange; beige after preservation
in ethanol.
Skeletal structure. There are polytylote subtylostyles
to subtylostrongyles (380–450 × 5–6 µm), erect on the
substrate with the points facing out, and acanthostyles
(430–470 × 10–12 µm).
Zoogeographic distribution. Widespread but uncommon.
In Alaska – Aleutian Islands. Elsewhere – Arctic
Ocean (Barents Sea, Laptev Sea, Kara Sea – Vilkitsky
Strait, and Greenland Sea) and North Atlantic Ocean
(between Faroe Islands and Iceland).
Habitat. In Alaska – attached to mollusk shells at a
depth of 146 m. Elsewhere – attached to rocks and
pebbles on sandy ooze at depths between 91 and 410
m, water temperatures of 1.47 to 1.17°C, and salinities
of 34.42 to 34.65 psu.
Photos. 1) Preserved specimen (in ethanol) attached
to a green false jingle (Pododesmus macrochisma) shell
collected at a depth of 146 m in the central Aleutian
Islands. Grid marks are 1 cm 2 . 2) Close-up view of same
specimen as in photo 1.
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