Modern corals are colonial; meaning each structure is actually made up of the shells of masses of tiny animals. Some members of the group Rugosa were instead solitary, growing orders of magnitude larger than any single living coral. Corals are cnidarians, a group that also includes jellyfish.
The tip of the ‘horn’ was shallowly buried in ocean floor sediments. This would lead to corals falling over on occasion due to strong currents; the animal would then build its shell towards the ‘new up’, which is why some rugose coral fossils are bent rather than straight shelled.
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Solitary Rugose Coral
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Themnopora (“feather duster coral)”
This is Thamnopora from Silurian limestone. Thamnopora is a branching tabulate coral. The name tabulate refers to the tabulae, horizontal
elements visible in longitudinal section. All tabulate
corals are colonial. -
Hexagonaria (compound rugose coral)
Hexagonaria has tabulate colonies with large numbers of small but massive corallites. The numerous thickened septa do not extend into the centre and are joined together by a wide dissepimentarium. In the calyx, above the tabularium, there is a deep, narrow depression. This Hexagonaria is from the Silurian.
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Solitary Rugose Coral
Modern corals are colonial; meaning each structure is actually made up of the shells of masses of tiny animals. Some members of the group Rugosa were instead solitary, growing orders of magnitude larger than any single living coral. Corals are cnidarians, a group that also includes jellyfish.
The tip of the ‘horn’ was shallowly buried in ocean floor sediments. This would lead to corals falling over on occasion due to strong currents; the animal would then build its shell towards the ‘new up’, which is why some rugose coral fossils are bent rather than straight shelled. -
Favosites (“Brain Coral”)
Favosites (“Brain Coral”) grows as giant domes or extensive thick crusts and can live for more than 100 years. It lived in warm, shallow water environments. Each Favosites is formed by genetically identical polyps which secrete a hard exoskeleton of calcium carbonate. Its hard outer shell, built by the tiny polyps that live within its walls, make it a type of stony coral. Hundreds of these polyps can live within a brain coral at one time. The polyps have two layers – an outer ectoderm and an inner endoderm, which are separated by a jelly-like mesogloea. They also have a single opening which acts as both mouth and anus, which is surrounded by a ring of tentacles containing stinging cells or ‘nematocysts’. The polyp mouths tentacles are only extended at night filtering small drifting organisms. This Favosite is from the Silurian.
http://en.wikipedia.org/wiki/Brain_Coral
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Solitary Rugose Coral
Modern corals are colonial; meaning each structure is actually made up of the shells of masses of tiny animals. Some members of the group Rugosa were instead solitary, growing orders of magnitude larger than any single living coral. Corals are cnidarians, a group that also includes jellyfish.
The tip of the ‘horn’ was shallowly buried in ocean floor sediments. This would lead to corals falling over on occasion due to strong currents; the animal would then build its shell towards the ‘new up’, which is why some rugose coral fossils are bent rather than straight shelled. -
Rugose Coral
Modern corals are colonial; meaning each structure is actually made up of the shells of masses of tiny animals. Some members of the group Rugosa were instead solitary, growing orders of magnitude larger than any single living coral. Corals are cnidarians, a group that also includes jellyfish.
The tip of the ‘horn’ was shallowly buried in ocean floor sediments. This would lead to corals falling over on occasion due to strong currents; the animal would then build its shell towards the ‘new up’, which is why some rugose coral fossils are bent rather than straight shelled. -
Solitary Rugose Coral
Modern corals are colonial; meaning each structure is actually made up of the shells of masses of tiny animals. Some members of the group Rugosa were instead solitary, growing orders of magnitude larger than any single living coral. Corals are cnidarians, a group that also includes jellyfish.
The tip of the ‘horn’ was shallowly buried in ocean floor sediments. This would lead to corals falling over on occasion due to strong currents; the animal would then build its shell towards the ‘new up’, which is why some rugose coral fossils are bent rather than straight shelled. -
Themnopora (“feather duster coral)”
This is Thamnopora from Silurian limestone. Thamnopora is a branching tabulate coral. The name tabulate refers to the tabulae, horizontal
elements visible in longitudinal section. All tabulate corals are colonial.http://home.gli.cas.cz/hladil/www/015.pdf
http://en.wikipedia.org/wiki/Tabulate_coral
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Graptolites
Graptolites were planktonic and floated in the upper part of the ocean waters. There external skeleton was made of organic material (chitine). Graptolites formed colonies by asexual reproduction.
Graptolites are seen prodominantly from the Cambrian Period (542 million to 488 million years ago) and that persisted into the Early Carboniferous Period (359 million to 318 million years ago). This Graptolite is from the Silurian. NSW, Australia.http://en.wikipedia.org/wiki/Graptolithinia
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Graptolithinia
Graptolites were planktonic and floated in the upper part of the ocean waters. There external skeleton was made of organic material (chitine). Graptolites formed colonies by asexual reproduction.
Graptolites are seen prodominantly from the Upper Cambrian through the Lower Carboniferous. This Graptolite is from the Silurian.http://en.wikipedia.org/wiki/Graptolithinia
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Graptolites
Graptolites were planktonic and floated in the upper part of the ocean waters. There external skeleton was made of organic material (chitine). Graptolites formed colonies by asexual reproduction.
Graptolites are seen predominantly from the Upper Cambrian through the Lower Carboniferous. This Graptolite is from the Silurian. -
Bryozoa-2
Polypora ehrenbergi. This Brtozoan formed in a funnel shaped. Like other \’Moss animals\’ this bryozoan was formed by small zooids that formed a colony. Fossil found along the South Coast of NSW.
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Bryozoa
Bryzoa are colonial animals that lived primarily in the sea. Every indevidual polypid or zooid in the colony secretes a calcareous, chitinous or membrane case around itself.
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Spiny Brachiopod
This brachiopod fossil is a rare example of the Spiny brachiopod Class: Lingulata (Order: Siphonotretida, stem group brachiopods)
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Bryozoan
Stenopora bryozoan was an aquatic invertebrate similar to coral but belong to a completely different phylum. They individual tubules of the ‘fan’ were inhabited by small colonial animals called zooids. The zooids were filter feeders that fed on organic particles washed around by the ocean currents. Specimen from the South Coast of NSW.