Surface of stone with delicate network of Telammina; note the tiny
chambers strung out along the very narrow tubes that make up the network.
This genus is common on hard substrates at many sites in the deep ocean
Despite initial appearances, deep-sea stones can be quite interesting. The ones that are exposed at the surface provide a hard substrate on which different creatures can settle, and are often teeming with life.
A stone with a brachiopod (Pelagodiscus) attached to the surface.
Also visible are two mat-like formations, one dark grey and
the other whitish in colour
Most foraminifera – forams – live in the soft sediment but others fix themselves to hard substrates. We found a wide variety of these attached forams on the stones.
Some were simple mud domes, others included extensive networks of fine tubules and flat mat-like formations. But the most common was a delicate net of minute tubules with tiny chambers positioned along them. Unlike most of the encrusting forams, this one has a name – Telemmina.
The stones provide sanctuaries on the seafloor for foraminifera and animals that could not survive in the sediment. In the Pacific Ocean, manganese nodules are often densely covered with similar organisms. Nodules are much less common in the Atlantic Ocean, so it’s fascinating to see the same kinds of foraminifera settling on stones that were transported from distant continents by icebergs thousands of years ago.
|An extensive network of fine tubules covers a large area of |
this stone, while on the left-hand side is a mat-like crust. Both are
assumed to be foraminifera.