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

71. Stelodoryx oxeata Lehnert, Stone and Heimler, 2006
Description. This species exhibits two growth forms.
One is a stalked, conical form with a ridged surface.
The other is a massively encrusting, lobate sponge with
a smooth surface. Consistency is rather hard and only
slightly elastic, due to the densely packed spicules in
the ectosome. The stalked specimen has a stalk of 2 ×
0.7 cm, and the body is 5 × 4 cm in greatest dimensions.
Color in life for both growth forms is greenish yellow
to light green.
Skeletal structure. SEM images of spicules are shown
in Appendix IV. Ectosome is densely packed with a tangential
arrangement of tornotes, peculiar shaped oxeas,
and microscleres. The choanosome consists in places
of an irregular reticulation of single spicules or short
spicule tracts. Megascleres are oxeas (517–558 × 20–
30 µm); the points of oxeas have a ragged, dented
outline. Tornotes have acanthose ends (230–270 × 9–
11 µm). Microscleres are large isochelae (54–110 µm),
medium-sized isochelae (23–32 µm), small anchorate
isochelae (9–13 µm), and thin centrotylote sigmas
(8–12 µm).
Zoogeographic distribution. Uncommon. In Alaska
– central Aleutian Islands. Elsewhere – not reported.
Habitat. Attached to cobbles and pebbles at depths
between 175 and 712 m.
Photos. 1) Specimen collected at a depth of 395 m
in the central Aleutian Islands. Grid marks are 1 cm 2 .
2) Specimen (indicated by the white arrow) collected
at a depth of 711 m in the central Aleutian Islands.
The separation between the red laser marks is 10 cm.
3) Specimen (top, center) collected at a depth of 175 m
in the central Aleutian Islands. The separation between
the red laser marks is 10 cm.
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