Tabulata

Syringopora sp.

• Worldwide

The tabulata are an extinct order of Hexacorallia who lived from the Ordovician to Late Permian. The name " tabulata " ( " floors coral " ) comes from the horizontal plates in the skeleton of the individual polyps (Latin tabulatus - paneled ). The 300 described exclusively colonial living genera of tabulata were in addition to the Rugosa the first Riffbildner among the flowers animals. Whether there was, as in the recent coral symbiosis with algae ( zooxanthellae ), is unknown. Their bloom, so the maximum of the number of species they came from Untersilur to the Upper Devonian. With the stromatoporoids and the Rugosa they formed in this period, the typical stromatoporoid - taboo Deferred reef systems.

In the Upper Devonian, due to strong sea level rises ( " Kellwasser Event") to the mass extinction of Rugosa and tabulata, vanished 90 % of the shallow-water and 50 % of deep-water forms. They did not recover it yourself. In the great mass extinction at the Permian / Triassic boundary they died like many other creatures from final.

Physique

The individual organisms of a colony are called Coral Israel and stand through pores or channels with each other. Inside they are divided by designated as Tabulae cross floors. In contrast to the Rugosa the septa ( longitudinal folds in the body interior ) are not fully formed, usually there are thorns or spines emanating from the interior walls. The outward form of the colonies can be very different, you know bulbous, spherical but also way branching forms. The individuals have on the surface of the colony cup openings, they were probably used as input and output for the filtration of the water. These openings were often only a few millimeters in size and mostly round in shape.

System

The different groups of tabulata can be distinguished, inter alia, by the shape of the septa and floors. A Fund of South Australia, the genus Moorowipora chamberensis from the Cambrian may possibly be put to the taboo distillates. This assignment is disputed, secured evidence comes only from the lower Ordovician. The Chaetetida are an extinct group of animals with calcium carbonate skeletons that were sometimes made to the taboo deferred corals, today they are mostly associated with the calcareous sponges.

Some examples of genera:

Sarcinula: They occurred only in the Ordovician and were found in Europe, North America and Asia.

Helio Lites: This genus existed from the Middle Ordovician to Middle Devonian and was spread worldwide. The colonies are usually formed spherical or mushroom-shaped. The tubes of Einzelinduvidien are surrounded by skeletal material and do not touch. They are connected by tubes, pores are never available. There are always six, usually thorn -shaped septa present.

Halysites: They were widely spread throughout the world, but it still lacks finds in South America. Their occurrence time was in Mittelordovizium to the Silurian.

Pleurodictyum: This genus was spread worldwide by the Lower to Middle Devonian. The special characteristic of this genus is the Hicetes, pierced a worm of the colony. Maybe there is a Synökie because the coral was offenstichtlich not severely damaged.

Favosites: You usually formed massive colonies with honeycomb-like calyx openings with a diameter of a few millimeters. They lived from the Upper Ordovician to the Middle Devonian.

Syringopora: This species is often found in the interior of fossil stromatoporoids, mostly in the genus Stromatopora. This is likely to commensalism, the Syringopora added the stromatoporoids apparently no harm.