One shipworm species is kinda odd; the giant shipworm. It’s a deep sea variety, the adult uses housed bacteria but these are chemosynthetic bacteria that break down sulphur compounds not wood. The young of this species do bore and eat wood. The giant shipworm is also the longest mollusk, reaching more than 1.5 meters.
I think it was the British navy that first adopted the use of copper to try to prevent the damage to their ships. Of course when ships started being made of other things shipworms were only a problem for wooden docks and pilings.
These clams are elongated, worm like (or vermiform), and therefore we can see where the ‘worm’ idea comes from. But again, they are clams, that is, in the class Bivalvia, and the Phylum Mollusca. They do have a pair of shells, compared to their body size their shells are much smaller than that of most clams. Bivalves are diverse in body size, Giant Clams (genus Tridacnaat more than 1 meter across) to the nearly microscopic pea clams (or check out the geoduck if you haven’t ever seen one), and shell shapes (just a few shown in the image below). Based on the variety maybe worm-like versions shouldn’t be so surprising.
Footnotes:
* I think these terms get a little overwhelming, is this part of the problem that science has—using words like xylotrophic when wood-eater, of wood-feeder, conveys the idea faster and better for nearly all readers. Is there a place for this terminology? Does it leave too many readers out? I’m both fascinated and frustrated with the mass of terminology that encompasses biology but I’m not sure I have an answer. Maybe, use it sparingly.
** Expeditions like this are so beneficial, there are still so many species out there that have not been ‘discovered’. Many species will become, and have become, extinct before we find/found them. Species extinctions alter ecosystems, causes ascetic loss, and could be helpful for humans in other ways (the cure for cancer could have been in that now extinct beetle).
*** Ruth Turner, noted shipworm expert, was also the first biologist to see deep sea hydrothermal vents.
Here she is at work:
References, just a few today:
These references are available online, open access. Go get em.
A quick FYI aside, if you don’t know about the Biological Heritage Library online, its great, especially for access to old materials.: https://www.biodiversitylibrary.org
This is the new species reference:
Shipway JR, Altamia MA, Rosenberg G, Concepcion GP, Haygood MG, Distel DL. 2019. A rock-boring and rock- ingesting freshwater bivalve (shipworm) from the Philippines. Proc. R. Soc. B 286: 20190434. http://dx.doi.org/10.1098/rspb.2019.0434
Here are a few more references:
Manitoba Museum blog entry:
https://manitobamuseum.ca/main/the-clam-that-sank-a-thousand-ships/
Turner, RD and Clapp WF. 1966. A Survey and Illustrated Catalogue of the
Teredinidae (Mollusca: Bivalvia). The Museum of comparative zoology. Harvard University. Cambridge Massachusetts.