Last week I gave you this specimen from the Dead Zoo to have a go at identifying:

There were some great suggestions, some alluding to the tusk-like shape and structure, but the first person with a correct identification was Tony Irwin with an anagram of “Kuphus“. If you’re not familiar with the Giant Shipworm Kuphus polythalamius (Linnaeus, 1758), it’s a genus of boring mollusc that has proved to be rather interesting.

It’s in the shipworm family, but until recently it was only known to science from large, empty tubes like this one that washed up on a few beaches in the Philippines. That all changed 2016 when some live specimens were found and researchers were able to take a closer look at the biology of these surprising animals.

Unlike other shipworm, it turns out that Kuphus doesn’t eat wood. Instead it burrows into sediment and has a symbiotic relationship with bacteria that live in its gills, which metabolise hydrogen sulphide. This is quite a big deal, since it seems to provide an example of one set of symbionts (those able to digest cellulose in other shipworms) being replaced by a very different set capable of metabolising inorganic chemicals.

This change in relationship allows Kuphus to utilise in a different habitat type and may provide a clue as to how some of the organisms present along mid-ocean ridges have managed to adapt to a habitat far away from sunlight and largely removed from normal organic inputs.

It’s odd to consider that this specimen has been in the Dead Zoo since 1879, but we never knew just how interesting the species is until so recently. I wonder what other revelations we’ll come across as we carry on with our decant?