Black
bath sponge
Family
Spongiidae
updated Oct 2016
Where
seen?
A black sponge that is sometimes seen on some of our shores, often
covered in sediments. These sponges are often seen on silty reef flats.
Features: Generally
a globular dome-shaped or loaf-shaped sponge up to 15cm, some with
lumps or knobs. Some have tiny holes, others with cones topped with
large circular holes. Texture finely granular, some smooth and shiny
especially underwater. Many are often covered in sediment. Colours
a uniform deep black. Sponges with these features which are commonly
encountered include Spongia ceylonensis, Spongia sp.
'Vulsella' and Hippospongia 'black massive'. They are difficult
to tell apart in the field.
The Black frogfish
(Family Antennariidae) resembles this sponge!
Sponging clams: Some Spongia species
are inhabited by Sponge
finger oysters (Vulsella sp.), a kind of clam that lives
only in sponges. These are completely and deeply embedded in the sponge,
with only a slit on the surface of the sponge where the bivalve's
shell opening is.
Members of the Family Spongiidaes have a skeleton made up of tough,
elastic fibres made of a protein called spongin. They lack the framework
of spicules (tiny, hard, sharp spikes) throughout their body.
Sometimes confused with the Black
prickly sponge (Echinodictyum conulosum) which has a very
prickly surface.
Human uses: Today, the sponges
you use at home are synthetic and not made from living sponges. In
the past, natural sponges were used for padding and packing, to paint
with and to bathe with. Natural sponges are still used today as luxury
bath items. Commercial bath sponges come mainly from Spongia officinalis
that is found in the Mediterranean Sea. Other species of the Family
Spongiidae may also be used for this purpose as these sponges produce
only spongin skeletons and do not have lots of sharp, poky spicules
like most other sponges. To make a bath sponge, the living sponge
is harvested, killed and processed to remove all the soft portions,
leaving behind the skeleton. The spongin itself cannot absorb water,
it is the structure of the skeleton that can absorb a huge amount
of water, which can be easily released when the skeleton is squeezed. |
Terumbu Pempang Laut, Aug 10
Terumbu Raya, May 10
|