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

68 Professional Paper NMFS 12
52. Artemisina sp.
Description. Aleutian Island specimens consist of
many large rounded lobes growing from a narrow base.
Large lobes often develop side-branches. Koltun (1959)
described this same species as funnel-shaped, thickly
tabular or massive. The surface is strongly rugose with
a thin ectosomal membrane. Circular oscula are flush
with the surface. It is soft and elastic but fragile. Size is
large with height to 40 cm and width to 60 cm. Color
in life varies from yellowish grey, light brown to orange;
typically golden yellow color in situ.
Skeletal structure. Ectosomal thin styles form a unispicular
reticulation with microscleres scattered in
between. Choanosomal multispicular tracts have large
styles and single spicules. Styles are often acanthaceous
at the base. There are large styles (490–840 × 15–30 µm),
small styles (210–480 × 7–10 µm), palmate isochelae
(12–22 µm), small toxa (30–120 µm), and large toxa
(280–340 µm).
Zoogeographic distribution. Locally abundant. In
Alaska – central Aleutian Islands. Elsewhere – Arctic
Ocean (Barents, Greenland, Kara, and Laptev seas).
Habitat. In Alaska – attached to bedrock, boulders,
and cobbles at depths between 80 and 195 m. Elsewhere
– reported at depths between 18 and 380 m.
Remarks. This is Artemisina apollinis sensu Koltun
(1959). However, A. apollinis was originally described
from near the Kerguelen Islands in the southern Indian
Ocean so conspecificity is unlikely. It is similar in
appearance to Mycale loveni with which it co-occurs, but
this species is much more heavily lobed than M. loveni
and narrows to a stout and narrow base. M. loveni is more
massive with a less defineable base. It may be preyed
upon by the sea star Henricia sp.
Photos. 1) Specimen collected at a depth of 195 m in
the central Aleutian Islands. Grid marks are 1 cm 2 . 2)
Specimen collected at a depth of 155 m in the central
Aleutian Islands. Grid marks are 1 cm 2 . 3) Specimen
observed at a depth of 122 m in the central Aleutian
Islands.