> Subphylum Vertebrate > fishes
learn only 3 things about them ...
They are fishes that go fishing! They use lures to attract
They are awkward swimmers, but they have the fastest mouth!
to spot: they resemble sponges, rocks. So watch your step!
These rotund fishes are sometimes seen on some of our shores. They
are probably quite common and often simply overlooked as they are
extremely well camouflaged.
What are frogfishes? Frogfishes
belong to the Family Antennariidae. According to FishBase,
the family has 12 genera and 41 species. These
fishes were previously called anglerfishes, a much more appropriate
name for these ambush predators. But anglerfish is now a common name
reserved for deep sea fishes that also use a lure to attract prey
within their reach.
Features: To about 18cm, but those encountered about 6-10cm
long. The frogfish has a rounded body that can expand greatly. A handy
feature that allows the fish to swallow prey as large as itself. Not
a fast swimmer, the frogfish usually lies motionless near coral rubble,
blending perfectly with its surroundings. Here it waits to ambush
passing prey. It doesn't have scales and instead, has a loose prickly
skin. Covered with filaments and fleshy bits, it looks just like an
Frogfishes come in a wide variety of colours and patterns. Some species
are brightly coloured to mimic sponges or other colourful reef creatures.
According to Kuiter, the young of some species of frogfishes sometimes
look like poisonous nudibranchs.
Sometimes mistaken for stonefish
and scorpionfish. Here's more on how
to tell apart fishes that look like stones.
with a lure: The
frogfish literally lures prey to come closer. The lure is at the top
of its head, just above its very large, upward facing mouth.The lure
is made up of the first spine of the dorsal fin. The spine is modified
into a rod or stalk (called the illicium) tipped with a fleshy, fluffy
or otherwise attractive bit (called the esca). This bit is wriggled,
jerked and waved about so it appears to be a helpless and tasty little
morsel. While the fish itself remains motionless, looking like just
another lump of rock or other harmless thing. Unsuspecting creatures
that attempt to eat the lure are instead eaten by the frogfish! Each
frogfish species usually targets a specific prey and each species
has a lure that resembles something the targeted prey would find tasty.
When not in use, the lure is safely flattened against the head.
The victim is usually swallowed whole in one gulp of the frogfish's
huge mouth. The frogfish can hugely expand its mouth in less than
a second, making it among the fastest capture in the animal kingdom.
What do they eat: Frogfishes generally
eat other fishes although some temperate species eat crustaceans.
They may even eat other frogfishes, including their potential mates!
Fish with arms?! The frogfish
has another unusual feature: limb-like pectoral fins with an elbow-like
joint. These look almost like 'paws'. It uses these fins almost like
arms and hands, to grip the surface and 'walk' slowly about (more
of a waddle actually). It also has clasping pectoral fins under its
The frogfish has tube-like gill openings under the base of its pectoral
fins. This prevents exhalations from betraying its presence. It is
said that the openings can also be used for jet-propelling. Its eyes
are at the top of its head. Gill openings are reduced to small round
Frogfish babies: A frogfish mother
lays thousands of eggs embedded in a large floating gelatinous mass
called an 'egg raft' or 'veil'. Several species carry their eggs attached
to their bodies.
Unusual frogfishes: While most
frogfishes are bottom-dwelling, one species (Histrio sp.) floats
among sargassum seaweed. Another species, the Brackishwater frogfish
(Antennarius biocellatus) inhabits brackish and even totally
Lure on the head
Limb-like pectoral fins
A large mouth!
Pulau Hantu, Jan 06
Very well camouflaged!
Tuas, Aug 04
on Singapore shores
Antennariidae recorded for Singapore
Wee Y.C. and Peter K. L. Ng. 1994. A First Look at Biodiversity
*Lim, Kelvin K. P. & Jeffrey K. Y. Low, 1998. A Guide to the Common
Marine Fishes of Singapore.
seen awaiting identification
caudimaculatus=**Antennarius commerson (Commerson's frogfish)
Antennarius chironectes=**Antennarius pictus (Painted frogfish)
Antennarius hispidus (Shaggy frogfish)
*Lophiocharon trisignatus (Spotted-tail