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

78. Cladorhiza bathycrinoides Koltun, 1955
Description. This stalked sponge terminates in a partially
inverted conical head. Basal root-like processes
consist of glassy, polyspicular tracts (2.5 cm long). Polyspicular
tracts of the root-like processes become united
at the base of the cylindrical stalk and are coated by a
thin ectosomal veneer. The circular upper plane of the
head has a diameter of 1.4 cm and thin appendages
(up to 12) are inserted along its margin. The appendages
measure 1.9 cm × 0.8 mm, but the diameter of
the appendages regularly varies like a string of pearls.
Typical of the genus, the polyspicular tracts of the
system of root-like processes are united at the base of
the stalk, run in bundles through the stalk, and then
diverge again to support the appendages. The height
from distal ends of the root-like processes to the upper
end of the head is up to at least 12 cm. The stalk is up
to 7 cm long and 1–2 mm in diameter. Color in life is
white or creamy white.
Skeletal structure. SEM images of spicules are shown
in Appendix IV. Ectosomal veneer is packed with anisochelae.
Fusiform styles (980–2100 × 12–40 µm) and
tylostrongyles (350–900 × 2–10 µm) are most abundant
at the distal parts of the root-like processes. There are
large anisochelae (55–75 µm), rare small anisochelae
(25–35 µm), large sigmas (95–110 µm), small sigmas
(43–55 µm), and flattened sigmoids with claw-like appendages
at the ends (42–45 µm). Large sigmas were
typically damaged in our SEM preparations indicating
that they are extremely thin-walled, hollow, and fragile.
Zoogeographic distribution. North Pacific Ocean.
Locally common. In Alaska – central Aleutian Islands;
patchy distribution at low densities. Elsewhere – Sea of
Okhotsk.
Habitat. In Alaska – on soft sediments (silt and sand)
at depths between 1108 and 2854 m. Elsewhere – eurybathic;
reported at depths between 150 and 3800 m.
Remarks. C. bathycrinoides probably has a carnivorous
feeding habit like other Cladorhizidae. We observed
one specimen in situ capture a small shrimp with one
of its appendages (actually the shrimp swam into the
appendage and appeared to adhere to it). Collected
specimens may have small crustaceans trapped in their
outer tissues.
95
Photos. 1) Specimen collected at a depth of 1371 m in
the central Aleutian Islands and held live in a shipboard
aquarium. Note the basal root-like processes. 2) Same
specimen as in photo 1 in situ. The separation between
the red laser marks is 10 cm.