Big
brown mactra clam
Mactra grandis
Family Mactridae
updated May 2020
Where
seen? This large brown clam is often seen on our Northern
shores in silty and sandy areas near seagrass. Usually alone, sometimes half buried in the ground.
According to Wong, it is perhaps the most commonly encountered member
of the Family Mactridae in Singapore. It was previously known as Mactra
mera.
Features: 6-7cm. The two-part
shell is thick, smooth and usually unmarked, in shades of plain brown
to purplish brown. It has a short siphon and usually lies buried just
beneath the surface with its siphon sticking out. Sometimes, though,
an unburied individual might be encountered on the shore. |
Changi, Jan
07 |
Pulau Sekudu,
May 12 |
Changi, Aug
12  |
| The Great Escape: The clam can use its foot to leap away from predators like the Noble volute and Moon snails. |
A clam using its foot to leap away
from a Moon snail.
Changi, Jul 11 |
Changi, Jan
07 |
| Big
brown mactra clams on Singapore shores |
| Other sightings on Singapore shores |
East Coast-Marina East, Jul 20
Photo shared by Vincent Choo on facebook. |
Changi East (Lost Coast), Jul 24
Photo shared by Kelvin Yong on facebook. |
Berlayar Creek, Apr 16
Photo shared by Loh Kok Sheng on flickr. |
St. John's Island, Apr 16
Photo shared by Loh Kok Sheng on his blog. |
|
Sisters Island, Aug 15
Photo shared by Heng Pei Yan on facebook. |
Sisters Island, Aug 15
Photo shared by Heng Pei Yan on facebook. |
|
|
Links
References
- Tan Siong
Kiat and Henrietta P. M. Woo, 2010 Preliminary
Checklist of The Molluscs of Singapore (pdf), Raffles
Museum of Biodiversity Research, National University of Singapore.
- Wong, H.
W., 2009. The Mactridae (Mollusca: Bivalvia) of East Coast Park,
Singapore. Nature in Singapore, 2: 283-296.
|
|
|
