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

43. Megaciella anisochela Lehnert, Stone and Heimler, 2006
Description. This sponge has clusters of 4–8 tubes with
a common stalk. The surface is finely hispid with no recognizable
oscula. The consistency is soft and elastic. The
dimensions of the short stalk are 2.0 × 0.5 cm and the
tubes are approximately 11 × 5 cm. Color in life is light
yellow; golden brown after freezing; beige in ethanol.
Skeletal structure. SEM images of spicules are shown
in Appendix IV. The ectosome is a thin translucent
membrane with tangentially arranged tylotes, singly or
in small bundles, facing in all directions within the tangential
plane. The ectosome contains many isochelae
and is supported by underlying styles. The choanosome
is a combination of a unispicular reticulation of single
spicules and ascending paucispicular tracts connected
by single spicules. Ascending tracts of styles penetrate
the ectosomal membrane and cause the hispidation.
Ectosomal tylotes (245–380 × 4–9 µm) have acanthose
heads. Smooth choanosomal styles measure 490–615 ×
18–22 µm. Microscleres are palmate isochelae (13–17
µm) with narrow extensions, a small category of palmate
isochelae (6–8 µm), and a small category of distorted
anisochelae (4–6 µm).
Zoogeographic distribution. In Alaska – locally abundant
in central Aleutian Islands. Elsewhere – not
reported.
Habitat. Attached to bedrock, boulders, and cobbles
at depths between 702 and 750 m.
Photos. 1) Specimen collected at a depth of 702 m
in the central Aleutian Islands. Grid marks are 1 cm 2 .
2) Same specimen as in photo 1 in situ.
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