fishes text index | photo index
Phylum Chordata > Subphylum Vertebrate > fishes > Family Monacanthidae
Fan-bellied filefish
Monacanthus chinensis*

Family Monacanthidae
updated Oct 2016

Where seen? This filefish is commonly seen on many of our shores, in sheltered areas with seagrasses and near reefs.

Features: To about 38cm, but those seen were 5-8cm long. Large triangular skin flap on the belly that can be greatly expanded, but often tucked close to the body. Body with lots of small circular dots and broad diagonal bars on the sides, in some these bars may be indistinct. It comes in all shades from brown to green. Tail fin with thin brown bands. On a large adult, the upper fin rays on the tail is produced into a filament.

More on how to tell apart filefishes.

What does it eat? It eats seagrass, seaweed and small crustaceans as well as immobile animals such as bryozoans, ascidians and hydroids.

Human uses: It is sold as seafood in some places.

Beting Bronok, Jul 03

Large belly flap

Usually with broad diagonal bars.
Chek Jawa, Jul 03

Filament on upper fin ray of the tail.

Tail fin with thin brown bands.

Some are tiny and resemble seagrass blades!
Changi, Jul 07

Large ones resemble coral rubble.
Chek Jawa, May 05

Tanah Merah, Oct 09

*Species are difficult to positively identify without close examination.
On this website, they are grouped by external features for convenience of display.

Fan-bellied filefishes on Singapore shores

Photos of Fan-bellied filefishes for free download from wildsingapore flickr

Distribution in Singapore on this wildsingapore flickr map

Berlayar Creek, Oct 15
Photo shared by Loh Kok Sheng on facebook.

Sentosa Serapong, Jul 15
Photo shared by Jonathan Tan on facebook.

Terumbu Semakau, Apr 13
Photo shared by Loh Kok Sheng on flickr.

Terumbu Raya, Aug 14
Photo shared by Loh Kok Sheng on his blog.



  • Allen, Gerry, 2000. Marine Fishes of South-East Asia: A Field Guide for Anglers and Divers. Periplus Editions. 292 pp.
  • Lieske, Ewald and Robert Myers. 2001. Coral Reef Fishes of the World Periplus Editions. 400pp.
FREE photos of
marine fishes.
Make your own badge here.
links | references | about | email Ria
Spot errors? Have a question? Want to share your sightings? email Ria I'll be glad to hear from you!
wildfactsheets website©ria tan 2008