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

84 Professional Paper NMFS 12
68. Myxilla (Myxilla) behringensis Lambe, 1895
Description. This sponge is massive and irregularly
globular. Surface is smooth. Consistency is slightly elastic
and rather firm due to the polyspicular tracts of the
choansosome. Diameter is to at least 4–5 cm. Color in
life is whitish to golden brown.
Skeletal structure. Tylotes (220–270 × 6–10 µm) are
ectosomal. Choanosomal acanthostyles (250–380 ×
10–15 µm) occur in a meshwork of polyspicular tracts.
There are anchorate large isochelae (70–80 µm), small
isochelae (15–18 µm), large sigmas (65–78 µm), and
small sigmas (27–32 µm).
Zoogeographic distribution. Widespread but rare in
the North Pacific Ocean. In Alaska – central Aleutian
Islands and Bering Sea. Elsewhere – Sea of Okhotsk,
Sea of Japan, and British Columbia (Vancouver Island).
Habitat. In Alaska – encrusts other demosponges at
depths between 190 and 195 m. Elsewhere – reported at
depths between 32 and 104 m and a salinity of 33.95 psu.
Remarks. In Alaska, the species is epizoic on the
demosponge Halichondria oblonga. It was considered by
Koltun (1958) as a subspecies of Myxilla incrustans.
Photo. 1) Specimen (center) collected at a depth of
195 m in the central Aleutian Islands. Grid marks are
1 cm 2 . Specimen is encrusting the demosponge Halichondria
oblonga.