Animalia Life
Monodactylus argenteus
FAMILY
Monodactylidae
TAXONOMY
Monodactylus argenteus Linnaeus, 1758, East Indies.
OTHER COMMON NAMES
English: Diamondfish, fingerfish, moony, silvery moony, Natal
moony; Japanese: Himetsubameuo.
PHYSICAL CHARACTERISTICS
Deeply compressed body with silvery color marked by a slender
dark-colored bar on the head. The anterior edges of the dorsal
and anal fins are also dark colored, the fins are pale yellow. The
pelvic fin is absent in adults. To 8.5 in (22 cm) total length.
DISTRIBUTION
Red Sea east to Samoa; Yaeyama Islands (southern Japan),
south to Australia and New Caledonia.
HABITAT
Brackish waters, estuaries, and silty reefs.
BEHAVIOR
Found singly or in small groups among mangroves or other
structures, but in large schools in estuaries and silty reefs
where they swim in the water column.
FEEDING ECOLOGY AND DIET
Feed upon plankton in the water column and detritus on the
bottom.
REPRODUCTIVE BIOLOGY
Spawns adhesive, demersal eggs in freshwater. Others in the
genus spawn pelagic eggs in seawater. Eggs are spherical and
approximately 0.039 in (1 mm) in diameter. The larvae hatch
around 0.071 in (1.8 mm) in length, are compressed and moderate
in depth, have a large yolk sac, an unformed mouth, and
unpigmented eyes. With growth, the head becomes large with
a convex dorsal profile that becomes steep over time. Possesses
a small gas bladder. Larvae have pelvic fins that are reduced in
adults. This character, plus the development of spines on the
head, are viewed as specializations for pelagic life.
CONSERVATION STATUS
Not listed by the IUCN.
SIGNIFICANCE TO HUMANS
Popular as an aquarium fish. Maybe taken in subsistence fisheries
as a food fish.