Wood burrows from a naval ship worm (Teredo navalis), X-ray

Digitally coloured X-ray of wooden timber previously housing a ship worm (Teredo navalis). Multiple tunnels (black) have been carved into the wood by this worm-like marine bivalve mollusc. Teredo navalis are specialised for wood boring and are the most common and destructive ship worm, causing permanent damage to wooden structures such as drift wood, boat hulls and piers. The inside of these characteristic winding burrows have circumferential markings. The grain of the wood is visible as vertical stripes (yellow). The width of the tunnels is approximately 6 mm in diameter.