Lingula is a Brachiopod that has been found in the fossil record from the Cambrian all the way up to today's ocean floors. It's a very primitive genera and that is probably a reason for it's longevity. Many animals specialize in a particular niche within the ecosystem. This makes them vulnerable to extinction when the environment changes or a food source disappears. Lingula have survived every major extinction event througout history because they are not picky about where they live or what they eat.
Lingula gets it's name from the similarity of it's shell to that of a small tounge (Lingulata, from the Latin word for "tongue"). They are inarticulate brachiopods which means their shells do not open and close along a hinge line. Rather they are pushed apart by a muscle within the shell thus allowing them to feed.
Here is a picture of a modern day Lingula from the Colorado State University
website.
For comparison, here is a Lingula from the Mahantango formation.
I have never found an Ord lingulid, though, I have found some other inarticulates.
ReplyDeleteI think I found one in the verulam material I brought back but have had the time to look closely yet. I've never seen one from the Cincinattian exposures.
ReplyDeletelingula belongs to the lophophorate phyla.... but why does its shell consist of CaPO4,unlike hte mollusc which are sedentary ?
ReplyDeleteAbesh, It's unknown why Lingula and it's close relatives the atremate brachiopods compose their shells from Calcium Phosphate. It certainly is unique among invertebrates but can be found within tooth enamel in Vertebrates.
ReplyDelete