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

2. Leucandra poculiformis Hozawa, 1918
Description. Sponge is thickly encrusting. The surface
is smooth to the unaided eye but rough to the touch due
to large protruding spicules. Consistency is stiff, slightly
compressible, and elastic. Individuals may reach a size
of approximately 6 × 2 × 1 cm. Color in life is white to
creamy white.
Skeletal structure. SEM images of spicules are shown
in Appendix IV. There are large triactines (50–170 ×
5–15 µm/ray) and occasionally tetractines of the same
dimensions. Small oxeas (60–85 × 3–6 µm) have unequal
ends, most with a characteristic bend near one
end. Small oxeas are only at the surface of inner and
outer walls, equiangular and sagittal triactines are inbetween.
Outer surfaces are covered by a mesh of small
diactines, mesh-size approximately 25 µm in diameter;
tracts form the mesh 20–40 µm in diameter.
Zoogeographic distribution. Rare. In Alaska – central
Aleutian Islands. Elsewhere – previously known only
from the Sea of Japan.
Habitat. Grows around and encrusts Stylaster hydrocorals
at depths near 175 m. Species of Craniella may be
attached to it (see photo 1).
Photos. 1) Whole specimen collected at a depth of
175 m in the central Aleutian Islands. Grid marks are 1
cm 2 . 2) The same specimen as in photo 1 in situ encrusting
a Stylaster hydrocoral.
13