268 Chapter 11
Infection of fresh wood occurs after completion of the reproductive process
followed by settlement and attachment of larvae to the wood surface. There is
some dispute about the need for larvae to crawl to regions of wood already
softened by superficial microbial decay, or whether they can burrow directly
into intact wood. In either case, the point on the surface of wood where a larva
begins burrowing is the animal’s only contact with the external environment
throughout its life. During periods of stress, e.g. temporary anaerobiosis or
exposure above the waterline, this fine aperture is plugged with a calcareous
pallet positioned close to the syphons. The morphology of the pallet varies from
spade-shaped to a series of ornamented cups and is an important diagnostic
Figure 1Diagram of an entire organism (Teredo) showing relative position of shell and siphons
(After Turner, 1971)
Figure 2X-ray radiograph of timber infested by Teredo sp.