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

67. Melonanchora globogilva Lehnert, Stone and Heimler, 2006
Description. This sponge is globular. The surface is
covered with numerous thin-walled, bulbous fistules,
4–8 mm high and up to 4 mm in width; widest at the
distal end. The ectosome is a translucent white layer, easily
detachable, 400–650 µm thick. Diameter is to about
10 cm. Color in life is light yellow with whitish, almost
translucent fistules.
Skeletal structure. SEM images of spicules are shown
in Appendix IV. The ectosome has smooth tylotes
partially arranged perpendicular to the surface but
oriented in all directions to some degree. From the
choanosome there are tracts of tylotes fanning out towards
the ectosome. Tylotes with acanthostyles are also
found in the choanosome. Tylotes are 640–680 × 10–
12 µm. Choanosomal acanthostyles (660–670 × 20–
30 µm) are singly distributed without recognizable orientation.
Microscleres are three categories of isochelae:
large isochelae with fimbriae (65–93 µm), large isochelae
of the same size but with dented outer margins, and
small anchorate isochelae (23–25 µm).
Zoogeographic distribution. Rare. In Alaska – central
Aleutian Islands. Elsewhere – not reported.
Habitat. Attached to pebbles and shell hash at a depth
of 173 to 190 m.
Photos. 1) Specimen collected at a depth of 190 m
in the central Aleutian Islands. Grid marks are 1 cm 2 .
2) Specimen (indicated by the white arrow) observed at
a depth of 179 m in the central Aleutian Islands.
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