What is a Fenestella fossil?
Fenestella, genus of extinct bryozoans, small colonial animals, especially characteristic of the Early Carboniferous Period (360 to 320 million years ago).
What is a bryozoan fossil?
Bryozoans (sometimes referred to as Entoprocta and Ectoprocta) are microscopic sea animals that live in colonial structures that are much larger than the individual animal. Bryozoans were so common in Kentucky’s ancient past that they may be the most common form of fossil found in the State.
What are bryozoan colonies?
Bryozoans are microscopic aquatic invertebrates that live in colonies. The colonies of different species take different forms, building exoskeletons (outer protective structures) similar to those of corals. Most colonies are attached to a structure such as a rock or submerged branch.
What is the function of the Zooecium in bryozoans?
In autozooids, and most other zooid types, the individual is surrounded in a tissue called a zooecium. The zooecium secretes calcium carbonate to form a skeleton in groups like the cheilostome Gymnolaemata, or gelatinous material in Phylactolaemata (learn more about these groups in the sections below).
What is an Archimedes fossil?
Archimedes is a fossil that looks like a screw. It is a genus of fenestrate bryozoans, defined by a corkscrew-shaped axial support column and spiraling mesh-like fronds attached to the column. Broken fragments of Archimedes are common in Mississippian rocks of both eastern and western Kentucky.
What does a bryozoan fossil look like?
Some bryozoans built colonies that grew from the seafloor in branching structures; these fossils look like something like twigs. Other species erected netlike frameworks, while some spread like a crust on shells, rocks, plants, and even other bryozoan colonies.
What does a bryozoan look like?
These tiny animals often colonize by branching out into shapes that look more like spaghetti than living animals. Bryozoans are made up of colonies of individuals, called zooids. Zooids are very tiny (less than one thirty-second of an inch), and come in shapes ranging from oval and box-like to vase-like and tubular.
What are bryozoan skeletons made of?
Most bryozoans have skeletons made of the mineral calcite but some cheilostomes are aragonitic and others employ a mixture of calcite and aragonite. Bryozoans have a U-shaped gut with a separate mouth and anus.
What is Zooecium made of?
Bryozoans are colonial animals and those from the type Cincinnatian consist of a series of calcite tubes that house individual bryozoan animals, as well as other structures. The entire colony is known as a zooarium, which is composed of multiple zooids. The skeleton of each is zooid is called a zooecium.
Is Archimedes an index fossil?
Archimedes is a genus of bryozoans belonging to the family Fenestellidae….Archimedes (bryozoan)
Archimedes Temporal range: | |
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Fossil stalks of Archimedes from Illinois, on display at Galerie de paléontologie et d’anatomie comparée in Paris | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Bryozoa |
Is it Fenestella or Fenestrellina?
In 1935 the name Fenestella M’Coy, 1844 was replaced by Fenestrellina, because it is a junior homonym of a bivalve, now considered synonymous with Anomia. In 1962 however, Fenestella was reinstated for the bryozoan genus. The misspelling Fenestrella became officially rejected.
What type of organism is a fan Fenestella?
Fenestella is a genus of bryozoans or moss animals, forming fan–shaped colonies with a netted appearance. It is known from the Middle Ordovician to the early Upper Triassic ( Carnian ), reaching its largest diversity during the Carboniferous.
How does Fenestella differ from other fenestellids with two rows of apertures?
Compared to other fenestellids with two rows of apertures, Fenestella is relatively fine, with large apertures and wide dissepiments. The distance between apertures in Fenestella remains the same as colonies grow and individuals (or zooids) will have had equal size lophophores.