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

19. Aulosaccus schulzei Ijima, 1896
Description. Vase-shaped sponge attaches basally to
solid substrate, thickest near its upper end. External
surface is smooth, completely lacking large projecting
spicules, and lined by a lattice of loose spicules. The
internal atrial surface has a network of diactin bundles
crossing the exhalant apertures, but a lattice of atrialia
is absent. There is a single large terminal osculum lacking
a marginal spicule fringe. Consistency is very soft
and easily torn. Height is up to 45 cm, diameter to 22.5
cm, and 34 mm in wall thickness. Color in life is creamy
white; drab when preserved.
Skeletal structure. Skeleton is composed entirely of
loose spicules. Megascleres are hypodermal pentactins
and a few triactins and tetractins (0.6–3.4 mm long
tangential rays; 0.9–4.4 mm long proximal rays); thick
diactins (3.3–17.7 mm long); thin diactins (1.4–6.7 mm
long); short atrial diactins (0.4–1.5 mm long); dermalia
are a mixture of stauractins, pentactins, and hexactins
(89–181 mm ray length); atrialia are mainly very large
hexactins with some pentactins (224–1186 mm ray
length). Microscleres include very large discasters, often
called “solasters” (513–1389 mm in diameter), with
primary rays fused into a slightly irregular sphere; very
thin oxyhexactins, with irregular variants, and hemioxyhexasters
(87–165 mm in diameter); small spherical
discohexasters (20–39 mm in diameter).
Zoogeographic distribution. Apparently a rare species.
In Alaska – central Aleutian Islands and Bering
Sea (Pribilof Canyon). Elsewhere – Japan, Kuril Islands,
Okhotsk Sea, and off southern California.
Habitat. In Alaska – in the central Aleutian Islands
it occurs on bedrock, boulders, and cobbles at depths
between 1270 and 1350 m. In Pribilof Canyon it occurs
at a depth of 300 m. Elsewhere – reported at depths
between 117 and 419 m.
Remarks. Associated fauna include juvenile lithodid
crabs (Paralomis verrilli and Lithodes couesi), panda-
lid shrimps, and the large ophiuroid Gorgonocephalus
eucnemis.
Photos. 1) Whole specimen collected at a depth of
300 m in Pribilof Canyon, Bering Sea. Grid marks are 1
cm 2 . 2) Specimen collected at a depth of 1320 m in the
central Aleutian Islands. 3) Same specimen as in photo
2 in situ. Two pairs of red lasers each separated by 10 cm.
33