Yesterday and today

Obviously, you have a better chance to see a fossil brachiopod - more than 25 000 species - than a living species. Their number dropped considerably. There are rather less species than in the past, not more than 350.

Yesterday

Example :

the fauna of the "Coral Rag of Bourges", France

These fossil brachiopods are characteristic of the upper Oxfordian (approx. 160 m. y.) layers surrounding a beginning reef. Nearly ten species populated the carbonated platforms in swallow warm water.

This picture shows a sample of faunal association :

Today

Example : brachiopods of New Zealand

These two specimens were collected in New Zealand. They are among to ten endemic species.

- The south of the South Island (Fjordland, Foveaux Strait...) is one of the rare places in the world where significant colonies of brachiopods still exist.

- The black shellis a specimen of Notosaria nigricans (Sow.) of the family of Rhynchonellidae. The pinkish one, on the other hand, is a variety of Terebratulidae. Its name is Calloria inconspicua (Sow.)

- Although the majority of the recent representatives of these two families live in deep water, sometimes until 1300m deep, some exceptions exist. It is the case of the fauna of Paterson Inlet, which is of great scientific interest : vagile species (Neothyris lenticularis Desh....), shallow water...

Lingula of yesterday and today

For a long time, the species Lingula was regarded as the typical example of a "living fossil", because it was believed that the morphology of its shell had not really evolved since the Cambrian period. However, this conservatism seems to be deceptive. According to certain specialists, notable differences exist between the ancient and the recent species (volume of the lophophorale cavity, length of the ventral channels of the mantle...) (Biernat & Emig, 1993).


Terebratulina retusa (Linné),
a recent species of European
distribution

Glossary

Endemic :a species found (breeding) only in one locality

Vagile : mobile fauna.

Dictionary
Biostratigraphy
Triassic
Cenozoic
Indentification
Yesterday and Today
Lower Jurassic
Recent
Classification
Paleoecology
Middle Jurassic
Glossary
Shell
Distribution
Upper Jurassic
Exchanges
Some more
Did you know it ?
Coral Rag
Links
Fossilization
Bibliography
LowerCretaceous
Ammonites
Epigeny
Paleozoic
Upper Cretaceous
E-mail