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

32 Professional Paper NMFS 12
18. Aulosaccus pinularis Okada, 1932
Description. Vase-shaped sponge attaches basally to
solid substrate, thickest near its upper end. External surface
is smooth and completely lacking large projecting
spicules; both external and internal surfaces are lined by
a lattice of loose spicules; there is a single large terminal
osculum without a marginal spicule fringe. Consistency
is very soft and easily torn. Height is to 24 cm, diameter
to 15 cm, and 23 mm in wall thickness. Color in life is
white; drab when preserved.
Skeletal structure. Skeleton is composed entirely of
loose spicules. Megascleres are thick diactins (4.4–5.6
mm long); thin diactins (1.3–5.5 mm long); pinular dermal
hexactins with projecting pinular ray (109–175 mm
long), tangential rays (103–150 mm long) and proximal
ray (86–140 mm long); pinular atrial hexactins with projecting
pinular ray (93–300 mm long), tangential rays
(109–214 mm long), and proximal rays (83–192 mm
long). Microscleres include very large discasters, often
called ”solasters” (193–438 mm in diameter) with fused
primary rays recognizable as six hemispherical bosses;
oxyhexasters and hemioxyhexasters (99–140 mm in diameter);
oxyhexactins (83–166 mm in diameter); small
spherical discohexasters (26–36 mm in diameter).
Zoogeographic distribution. Rare. In Alaska – central
Aleutian Islands. Elsewhere – western Bering Sea,
Kuril Islands and off the southern tip of the Kamchatka
Peninsula.
Habitat. In Alaska – attached to bedrock, mudstone,
or boulders at depths between 843 and 1715 m. Elsewhere
– reported at a depth of 117 m but most collections
do not report depth.
Photos. 1) Mostly intact specimen collected at a depth
of 843 m in the central Aleutian Islands. Grid marks
are 1 cm 2 . 2) Same specimen as in photo 1 in situ. Note
that the specimen has been torn on the left side (prior
to collection) and the osculum is directed to the right.