AMHERST — A worm-like freshwater clam in the Philippines’ Abatan River has a fascinating diet. The organism, which locals call “antingaw,” eats rock as it burrows into the river bed, expelling sand out the other end.
A group of international scientists, including a University of Massachusetts post-doctoral researcher, recently identified the creature as an entirely new species and genus of shipworm — an animal normally known for its consumption of wood.
“It’s the first shipworm that’s ever been found that doesn’t live in wood for a least one cycle of its life,” said Reuben Shipway, the UMass microbiology post-doc. “It’s taking the bedrock of this river and it’s eating it and it’s passing it through it’s system… It’s basically pooping out sand.”
Of course, the scientists didn’t “discover” anything; locals have always known about the creature, and new mothers eat them to enhance lactation, Shipway said.
“The local people have known about this species for ages, and we’ve only just formally described it and let the wider scientific community know,” he said.
But after “DNA barcoding” the creature, and analyzing its anatomy using a micro-CT scan, the international team of researchers known as the Philippine Mollusk Symbiont International Collaborative Biodiversity Group determined that the new shipworm should be considered not only a new species, but also a new genus — the taxonomic rank above a species.
The researchers have given the new shipworm the scientific name Lithoredo abatanica, which comes from the Latin word for rock and the name of the river in which they live.
Normally, shipworms use their shells to burrow into wood, which they digest with the help of symbiotic bacteria, which produce enzymes that have helped scientists discover, among other things, potential information to help in the creation of new drugs like antibiotics.
How Lithoredo abatanica digest rock is still unknown, as is how the creatures get their nutrition.
The team introduced their research this week in the journal Proceedings of the Royal Society B. Shipway said the findings are important because of their contribution to scientific knowledge of the planet’s biodiversity, as well as what they could mean for the research group’s goals.
“The whole aim of this research is to look at biodiversity, look at the symbionts that are associated with this biodiversity, and develop new drugs and drug compounds from these bacteria,” he said. “When you find interesting biology, it usually means the animal has interesting chemistry.”
Beyond those implications, Shipway said that it was stunning to witness the shipworms’ behavior. The way that they bore into rock actually changes the course of the river, he said. And when the shipworms die, their tunnels provide rich environments for other creatures to live.
The fact that the creatures live in freshwater is also remarkable, Shipway added.
That knowledge could provide insights for paleontologists, who have seen fossil borings in rock before and thought they were markers of ancient marine habitats. But the Lithoredo abatanica could mean that those fossils could also be from ancient freshwater sites, too.
Dusty Christensen can be reached at dchristensen@gazettenet.com.