Did Tridacna gigas Linnaeus, 1758 ever occur in Singapore? It is the largest in the family Tridacnidae, reaching to one and a half metres.
Singapore is home to four other species of giant clams. According to Tan & Woo, 2010 [A Preliminary Checklist of the Molluscs of Singapore], the giant clam species in our waters are :
- Hippopus hippopus (Linnaeus, 1758) (bear paw or horse’s hoof clam),
- Tridacna crocea Lamarck, 1819 (the burrowing giant clam),
- Tridacna maxima (Röding, 1798) (the small giant clam) and
- Tridacna squamosa Lamarck, 1819 (the fluted giant clam)
(Species links are to WildSingapore Fact Sheets.)
So I was tickled to see this photo last week from the University of Washington Libraries’ Freshwater and Marine Image Bank which features images scanned by the staff of the Fisheries-Oceanography Library.
This image was from page 232 of Whymper, F., 1884. Fisheries of the World: an Illustrated and Descriptive Record of the International Fisheries Exhibition, 1883. Casseil & Co. Ltd., London, viii + 376 p. Th caption reads “Great Oyster from Singapore; (Tridacna gigas.); This is the finest known specimen, and to it the Jury awarded a diploma at the Fisheries Exhibition. Its weight is 3 cwt. 3 qrs. 14 lbs.; its length 3 ft. 4 in.; and its breadth 2 ft.; 2 in.
Excitement aside, this simply means there were two shells on display at the Gardens of the Royal Horticultural Society, South Kensington, London, from 12 May – 30 October 1883 for the International Fisheries Exhibition. They were labelled to be “from Singapore”, but are we to belief a fisherman’s tale about their origins?
Singapore, has been at the centre of regional and international trade for a long time, so claims about wildlife origins in the days before regulation have to be extensively checked. To make this complicated, giant clams were not uncommon near kampungs where they were variously used as containers presumably after the meat of the mollusc had been consumed.
In some instances, we will never unravel the truth about some facts. But its nice to see more material from old tomes surface on the internet, to challenge and contribute to our understanding.