Pineconefishes
Contributed by Steve Griffin
These
non-aggressive fish are named for there pinecone or pineapple like appearance.
They are nocturnal feeders and can usually be found alone or in a pair under
ledges or inside caves during the day.
To assist in attracting the small shrimp which are their usual diet, pinecone
fishes have light organs located on both sides just below the lower jaw. These
light organs activate symbiotic phosphorescent bacteria which create a greenish
glow in the dark. As the fish age the colour of the light is reported to change
to red.
Two
species of Pineconefish are found in Australia.
The Japanese Pineconefish (Monocentris japonicus) is yellow in colour
with black scale margins. It grows to around 17 cm and its scales form a bony
carapace. Its light organs are small and rectangular in shape. They are generally
found in 15 - 200m. They have been found in numerous locations around the world
including the Red Sea, South Africa, Mauritius, Sri Lanka to Australia, Japan
to North New Zealand.
The
Pineapplefish (Cleidopus gloriamaris) is named for its pineapple-like
appearance. This species has been reported only in the east and west coasts
of Australia with no reports from Victoria, Tasmania or South Australia. It
is yellowish in colour with dark scale margins and grows to around 25cm in length.
Its light organs are some what larger than those of M. japonicus and
are more ovular in shape. They are found in rocky and coral reefs in 5 - 50
m. The Pineapplefish is also known as the Knightfish.