1. CNIDARIA Phylum: Cnidaria: (formerly called Coelenterata) Class: Anthozoa: (corals) Hydrozoa: (hydroids) Scyphozoa: (jellyfish) Sub-Classes:Zoantharia: Rugosa (extinct) Tabulata (extinct) Scleractina (reef building, still exist part of the Zoantharia).

2. The polyps are solitary or colonial. The polyps are solitary or colonial. The soft parts are divided into 6, 8 or more. The soft parts are divided into 6, 8 or more. Often have a bilateral symmetry. Often have a bilateral symmetry. Marine. Marine.

3. ANTHOZOAN MORPHOLOGY: Corals are usually sack shaped widest at the top which contained the MOUTH narrowing at the base where it was attached. Corals are usually sack shaped widest at the top which contained the MOUTH narrowing at the base where it was attached. Page 101 Copy Fig. 63a. Page 101 Copy Fig. 63a. Draw c and h on page 103 for a typical solitary coral. Draw c and h on page 103 for a typical solitary coral. The body structure is simple with a hard calcite outer layer and an inner body cavity. The body structure is simple with a hard calcite outer layer and an inner body cavity.

4. SOFT PARTS: The soft parts are similar in all the subclasses. The soft parts are similar in all the subclasses. Page 114 Black Fig. 72a and b (draw). Page 114 Black Fig. 72a and b (draw). The body cavity is divided into small segments by RADIAL MESENTERIES (partitions) which give it stability and strength and provide more efficient feeding. The body cavity is divided into small segments by RADIAL MESENTERIES (partitions) which give it stability and strength and provide more efficient feeding. Outer Layer = ECTODERM Outer Layer = ECTODERM Inner Layer = ENDODERM Inner Layer = ENDODERM The inner body cavity = COELENTERON (ENTERON) The inner body cavity = COELENTERON (ENTERON)

5. Mesenteries help spread the surface area of the coelenteron and therefore help digestion of food. Mesenteries help spread the surface area of the coelenteron and therefore help digestion of food. The MOUTH is usually towards the centre and has a number of functions: The MOUTH is usually towards the centre and has a number of functions: 1. Takes in food. 2. Allows discharge of waste. 3. Discharge of larvae. The mouth is surrounded by retractable tentacles, which have stinging organs on them. The mouth is surrounded by retractable tentacles, which have stinging organs on them. Some corals show a bilateral symmetry but more commonly show radial symmetry with parts of the body repeated in the coelenteron around the mouth. Some corals show a bilateral symmetry but more commonly show radial symmetry with parts of the body repeated in the coelenteron around the mouth.

6. Middle Ordovician - Permian. Middle Ordovician - Permian. Occur as solitary or compound forms. Occur as solitary or compound forms. SOLITARY RUGOSE CORALS: Coraliteis conical in shape. Coraliteis conical in shape. The skeleton grew upwards from a narrow base. The skeleton grew upwards from a narrow base. The whole structure can be straight or curved (horn shaped). The whole structure can be straight or curved (horn shaped).

7. CALICE or the top of the body appears like a depression and in this can be seen a central region called the AXIAL REGION. CALICE or the top of the body appears like a depression and in this can be seen a central region called the AXIAL REGION. The ends of the SEPTA can also be seen sometimes. The ends of the SEPTA can also be seen sometimes. A COLUMELLA may be present in the centre (rod like) A COLUMELLA may be present in the centre (rod like)

8. Colonial/Compound Rugose Corals In colonial rugose corals there are often a large number of septa. In colonial rugose corals there are often a large number of septa. TABULAE: These represent former levels of the calice floor, secreted by the polyp to seal off the lower area of the corallum. TABULAE: These represent former levels of the calice floor, secreted by the polyp to seal off the lower area of the corallum. They are best seen if longitudinal sections are cut. They are best seen if longitudinal sections are cut.

9. Colonial/Compound Rugose Corals They are made up of varying numbers of individuals each called a corallite. Fig. 63 page 101 (OHP). They are made up of varying numbers of individuals each called a corallite. Fig. 63 page 101 (OHP). They are subdivided based on the relationship between the corallites: They are subdivided based on the relationship between the corallites:FASCICULATE: The individuals are not closely touching. The individuals are not closely touching. Fasciculate corals can be further sub divided: Fasciculate corals can be further sub divided:DENDROID: They branch irregularly. They branch irregularly.PHACELOID: If the corallites are parallel to each other. If the corallites are parallel to each other.

10. Colonial/Compound Rugose Corals MASSIVE: All the corallites are in contact. All the corallites are in contact. These are also further sub divided: These are also further sub divided:CERIOID: Polygonal corallites in cross section and they have a clear dividing wall. Polygonal corallites in cross section and they have a clear dividing wall. ASTRAEOID: The walls are absent. The walls are absent.

11. Sessile apart from when in larval stage. Sessile apart from when in larval stage. Benthonic and fixed. Benthonic and fixed. lived in warm (22 - 29ºC ideally 25ºC) tropical. lived in warm (22 - 29ºC ideally 25ºC) tropical. Shallow seas ideally <25 m continental shelf. Shallow seas ideally <25 m continental shelf. They like clear water with little sediment. They like clear water with little sediment. Well oxygenated, high energy. Well oxygenated, high energy. Typically found in carbonate rocks especially in the Carboniferous. Typically found in carbonate rocks especially in the Carboniferous. Mode of life and palaeoenvironment (Index Fossil)

12. Appear in the middle of the Ordovician but are not common until the Silurian. Appear in the middle of the Ordovician but are not common until the Silurian. Throughout the rest of the Palaeozoic their numbers increased. Throughout the rest of the Palaeozoic their numbers increased. They reached their maximum in the Lower Carboniferous and then gradually declined and disappeared in the Permian extinction. They reached their maximum in the Lower Carboniferous and then gradually declined and disappeared in the Permian extinction.

13. These are extinct compound corals. These are extinct compound corals. They have slender corallites, which are crossed transversely by tabulae. They have slender corallites, which are crossed transversely by tabulae. They have a calcareous skeleton with usually small individual corallites although the whole colony can be large. They have a calcareous skeleton with usually small individual corallites although the whole colony can be large. Shape: either fasciculate (no contact) or massive. Shape: either fasciculate (no contact) or massive.

15. The fasciculate forms can branch irregularly. The fasciculate forms can branch irregularly. In others the corallites are joined laterally to form a chain like structure approximately one corallite wide. In others the corallites are joined laterally to form a chain like structure approximately one corallite wide. The calice is usually small being a few mm in diameter and varying in shape : round, oval or polygonal. The calice is usually small being a few mm in diameter and varying in shape : round, oval or polygonal. The septa are not always present but number about 12 if they are present and they are similar in size and shape. The septa are not always present but number about 12 if they are present and they are similar in size and shape. Tabulae are very numerous and occur horizontally although some appear domed. Tabulae are very numerous and occur horizontally although some appear domed. Mural pores: small holes that connect the corallite Mural pores: small holes that connect the corallite

16. Tabulate Corals To Know Favosites: Favosites: Upper Ordovician - Devonian. Upper Ordovician - Devonian. Draw: Draw: Halysites: Halysites: Ordovician to Silurian. Ordovician to Silurian. Draw: Draw:

17. FAVOSITES: Massive corallum, often a hemisphere shape. Massive corallum, often a hemisphere shape. The whole colony is usually fairly small, maximum being 10 cm across, rarely larger. The whole colony is usually fairly small, maximum being 10 cm across, rarely larger. Cerioid (polygonal) corallites which are often quite long. Cerioid (polygonal) corallites which are often quite long. Each calice is small: 2 - 3 mm in diameter. Each calice is small: 2 - 3 mm in diameter. The septa are often absent, if present they form ridges. The septa are often absent, if present they form ridges. Tabulae are numerous and evenly spaced. Tabulae are numerous and evenly spaced. Most important in the Silurian. Most important in the Silurian.

18. HALYSITES: Phaceloid corallum giving an almost chain like appearance as corallites can be joined together on two or three sides to form a branching structure. Phaceloid corallum giving an almost chain like appearance as corallites can be joined together on two or three sides to form a branching structure. Commonly called “chained coral”. Commonly called “chained coral”. Septa are usually absent and the tabulae are horizontal. Septa are usually absent and the tabulae are horizontal.

19. Middle Ordovician to Permian extinction. Middle Ordovician to Permian extinction. Most abundant in the Silurian and Devonian, then through the Upper Palaeozoic the numbers decreased and died out in the Permian extinction. Most abundant in the Silurian and Devonian, then through the Upper Palaeozoic the numbers decreased and died out in the Permian extinction. Most common in carbonate rocks e.g. limestone, rarely found in muddy sediments. Most common in carbonate rocks e.g. limestone, rarely found in muddy sediments. During the Silurian and Devonian important reef formation and during this time they were more numerous than rugose corals. During the Silurian and Devonian important reef formation and during this time they were more numerous than rugose corals. Silurian: Favosites and Halysites common. Silurian: Favosites and Halysites common. Devonian: Favosites still common. Devonian: Favosites still common.

20. Solitary or compound corals. Solitary or compound corals. Some still exist. Some still exist.

21. Draw figs 73 f and h Black page 116. Draw figs 73 f and h Black page 116. Their originally aragonitic skeletons have dissepiments, tabulae, and septa just as in the rugosa. Their originally aragonitic skeletons have dissepiments, tabulae, and septa just as in the rugosa. Although there are superficial similarities, scleractinian corals differ from rugosa corals by their skeletal mineralogy and by their method of septal insertion during growth. Although there are superficial similarities, scleractinian corals differ from rugosa corals by their skeletal mineralogy and by their method of septal insertion during growth.

22. Scleractinian corals also have six primary septa, but in contrast to rugose corals, subsequent septa are added in all six of the resulting spaces. Scleractinian corals also have six primary septa, but in contrast to rugose corals, subsequent septa are added in all six of the resulting spaces. An important distinction between the two orders is that for the Scleractinia the septa are inserted between every two pre-existing septa in later growth stages. An important distinction between the two orders is that for the Scleractinia the septa are inserted between every two pre-existing septa in later growth stages. Therefore have a repeated radial symmetry and so different from the Rugosa. Therefore have a repeated radial symmetry and so different from the Rugosa.

23. Adjacent polyps can be attached or connected together via common soft tissue. Adjacent polyps can be attached or connected together via common soft tissue. They resemble sea anemones. They resemble sea anemones. The corallum of the solitary corals is usually conical or cylindrical. The corallum of the solitary corals is usually conical or cylindrical. In compound types there is a much wider range of sizes and shapes. In compound types there is a much wider range of sizes and shapes. Use the same terminology as used in rugose corals. Use the same terminology as used in rugose corals.

24. Middle Triassic to Recent. Middle Triassic to Recent. Most important in the Jurassic. Most important in the Jurassic. Not very important in the Cretaceous but can be found in the Chalk in particular solitary forms. Not very important in the Cretaceous but can be found in the Chalk in particular solitary forms. In the Tertiary there are a few reef-building forms and more recently in the Quaternary cup like corals are more common. In the Tertiary there are a few reef-building forms and more recently in the Quaternary cup like corals are more common. In the present they form important reef building animals in the tropics and sub tropics around ocean islands and east coasts of large landmasses. In the present they form important reef building animals in the tropics and sub tropics around ocean islands and east coasts of large landmasses.