sponge green seaweed
updated Oct 2016
This woolly branching seaweed is often seen on many of our Southern
shores, growing on coral rubble.
Features: The entire organism
can be about 20-30cm across (to 50cm), with 'stems' about 0.5-1cm
wide. 'Stems' may be short knobs, long cylindrical or flattened, or
even flattened leafy shapes. Tips usually thin and tapering, usually
not Y-shaped. Each 'stem' is made up of fine, branched filaments that
are packed together to form structures that feel woolly, velvety,
spongey or felt-like. The 'stems' are smooth and do not have obvious
holes in them, especially when the sponge is out of water. Light to
This organism is actually a symbiotic combination of an algae (Cladophoropsis
vaucheriaeformis) and a sponge (Halichondria cartilaginea,
Family Halichondriidae)! The sponge cells and spicules are intertwined
with the algae.
Sometimes confused with the Holey
sponge seaweed (Ceratodictyon sp.) which has more obvious
'holes' along the 'stems'. It is a red seaweed which also has a symbiotic
relationship with another kind of sponge. The two organisms are sometimes
difficult to tell apart in the field.
No obvious holes.
Terumbu Semakau, Dec 11
Terumbu Salu, Jan 10
Pulau Tekukor, Jan 10
Pulau Jong, Jul 06
*Species are difficult to positively identify without close examination
of internal parts.
On this website, they are grouped by external features for convenience of
sponge green seaweeds on Singapore shores
Berlayar Creek, Oct 17
Photo shared by Abel Yeo on facebook.
Pulau Semakau East, Jan 16
Photo shared by Lisa Lim on facebook.
Terumbu Berkas, Jan 10
Pulau Sudong, Dec 09
Pulau Biola, Dec 09
Pulau Biola, Dec 09
Pulau Salu, Aug 10
Terumbu Semakau, May 10
- Lee Ai Chin, Iris U. Baula, Lilibeth N. Miranda and Sin Tsai Min ; editors: Sin Tsai Min and Wang Luan Keng, A photographic guide to the marine algae of Singapore, 2015. Tropical Marine Science Institute, 201 pp.
- Lim Swee
Cheng, Nicole de Voogd and Tan Koh Siang. 2008. A
Guide to Sponges of Singapore. Singapore Science Centre.
- A. C. Lee, Lawrence M. Liao
and K. S. Tan. New records
of marine algae on artificial structures and intertidal flats
in coastal waters of Singapore. Pp. 5-40. in the Raffles Bulletin of Zoology
- Pham, M.
N., H. T. W. Tan, S. Mitrovic & H. H. T. Yeo, 2011. A
Checklist of the Algae of Singapore, 2nd Edition. Lee Kong Chian Natural History Museum, National University of Singapore,
Singapore. 99 pp. Uploaded 1 October 2011.
John M. 2000. Marine
Plants of Australia University of Western Australia Press. 300pp.
H. P. & Menez, E. G., 1997.Field
Guide to the Common Mangroves, Seagrasses and Algae of the Philippines.
Bookmark, Inc., the Philippines. 197 pp.
- Trono, Gavino.
C. Jr., 1997. Field
Guide and Atlas of the Seaweed Resources of the Philippines..
Bookmark, Inc., the Philippines. 306 pp.