Fossil Fact File/Halysites
From GeoWestMidlands
Contents |
‘Chain Coral’
What is it?
Chain Coral (scientific name Halysites) is one of the many types of fossil coral skeleton that can be found in the limestones of Dudley. It is like a series of limestone tubes or straws that are joined side-by-side. End-on these tubes look like links of chain. Inside each tube lived a jelly-like coral animal (polyp) very much like coral animals today. The chain coral belongs to a group of animals called Coelenterates. As they grew they built up the walls of the tubes (theca) and multiplied so adding more links to the chain.
How and where did it live?
Corals are one of the best fossil groups for telling us about the ancient world. Corals today mainly live in warm, shallow, clean seawaters where there is plenty of sunlight. This tells us that millions of years ago Dudley was covered by a warm shallow tropical sea. Corals like Halysites have a ring of stinging tentacles around their edge that capture food swimming or floating in the seawater that washes over them. As they grow and multiply they build large limestone reef structures on the seabed.
When did it live?
It lived in a time that scientists call the Silurian Period (which is named after a tribes of ancient Britons called the Siluries who lived across Shropshire and into Wales). In Dudley, it is found in beds of rock called the Much Wenlock Limestone Formation. These are between 416 and 423 million years old.
Where can I Find One?
| Facts at a glance | |
|---|---|
| Common Name: | Chain Coral |
| Species Name: | Halysites catenularia |
| Kingdom: | Animal |
| Phylum: | Coelenterata |
| Family: | Anthozoa |
| Genus: | Halysites |
| Period: | L. Palaeozoic, Silurian |
| Age: | 416 to 423 million Years |
These fossils can now sometimes be found in the Limestones of Dudley, West Midlands where the old mines and quarries have left behind rock exposures at the surface. Please note; Collecting from fallen blocks is permitted on most of these sites but hammering the rock faces is forbidden.
