Tridacna: Marine Biologists Find New Species of Giant Clam

Nov 22, 2013 by Sci-News.com

Scientists have discovered a previously undescribed species of giant clam on coral reefs in the Indo-Pacific region.

Tridacna maxima, a close relative of the newly discovered giant clam. Image credit: Karelj.

Tridacna maxima, a close relative of the newly discovered giant clam. Image credit: Karelj.

The yet-to-be-named species belongs to Tridacna, a genus of large saltwater clams.

“Giant clams can grow up to 230 kg and are some of the most recognizable animals on coral reefs, coming in a spectrum of vibrant colors including blues, greens, browns and yellow hues,” explained Jude Keyse, a postgraduate student at the University of Queensland, Australia.

Giant clams are beloved by divers and snorkelers but also prized as a source of meat and shells. Overconsumption by humans has depleted giant clams populations in many areas and most giant clam species are on the International Union for Conservation of Nature Red List of Threatened Species.

Ms Keyse, who is a co-author of the paper published in the open-access journal PLoS ONE, with colleagues non-lethally collected samples of tissues from giant clams at 0 – 20 m depth in the waters near the Solomon Islands and at Ningaloo Reef in Western Australia.

This image shows the newly discovered Tridacna clam. Image credit: E. A. Treml.

This image shows the newly discovered Tridacna clam. Image credit: E. A. Treml.

“DNA sequences strongly suggest that a distinct and unnamed species of giant clam has been hiding literally in plain sight, looking almost the same as the relatively common Tridacna maxima,” Ms Keyse said.

“To correctly describe the new species now becomes critical as the effects of getting it wrong can be profound for fisheries, ecology and conservation,” said co-author Shane Penny, a postgraduate student at Charles Darwin University.

______

Bibliographic information: Huelsken T et al. 2013. A Novel Widespread Cryptic Species and Phylogeographic Patterns within Several Giant Clam Species (Cardiidae: Tridacna) from the Indo-Pacific Ocean. PLoS ONE 8 (11): e80858; doi: 10.1371/journal.pone.0080858