Archaeocyathan knowledge base (Cambrian)

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Orbicyathus

Orbicyathus VOLOGDIN, 1937b

Specimen-type: Orbicyathus mongolicus holotype, VOLOGDIN, 1937a, pl. 2, fig. 4

Systematics:
Order: AJACICYATHIDA R. Bedford& J. Bedford, 1939
Suborder: AJACICYATHINA R. Bedford& J. Bedford, 1939
Superfamily: BRONCHOCYATHOIDEA R. Bedford& J. Bedford, 1936
Family: AJACICYATHIDAE R. Bedford& J. Bedford, 1939

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Outer wall

• Shape of carcass perforations openings (OW/SW) : Simple only
• Presence of carcass external plates: outer wall or single wall (OW/SW) : None
• Size of carcass pores (OW/SW) : Uniform size
• Repartition of carcass pores (OW/SW) : Homogeneous repartition
• Type of carcass perforations: outer wall or single wall (OW/SW) : Pores
• Presence of carcass bumps: outer wall or single wall (OW/SW) : None
• Presence of stipules (OW/SW) : None
• Shape of morphological tubes (OW/SW) : None
• Structure of outer carcass wall (OW/SW) : Carcass wall well defined
• Repartition types of carcass pores (OW/SW) : Straight rows of pores
• Type of additional sheath (OW/SW) : None
• Rows number of carcass perforations per intersept (OW/SW) : 2 AND more than 2 rows per intersept
• Subdivision of carcass perforations openings (OW/SW) : Without subdivision

Inner wall

• Shape of carcass perforations openings (IW) : Simple
• Rows number of carcass pores per intertabula (IW) : Several rows of pores between two successive tabulae only ; No tabula
• Type of carcass perforations: inner wall (IW) : Pores
• Building of carcass perforations (IW) : Without participation of vertical structures
• Presence of carcass external plates: inner carcass wall (IW) : None (external plates and/or inner wall)
• Shape of morphological tubes (IW) : None
• Structure of inner carcass wall (IW) : Carcass wall well defined
• Type of additional sheath (IW) : None
• Presence of stipules (IW) : None
• Rows number of carcass perforations per intersept (IW) : More than 2 rows per intersept only
• Subdivision of carcass perforations openings (IW) : Without subdivision

Intervallum

• Presence of intervallar cells : None
• Type of links between intervallar structures : None
• Presence of vertical intervallar structures : Present
• Presence of tabulae : Present ; none
• Type of vertical intervallar structures : Septa
• Pores shape of tabulae : Pecten
• Repartition of vertical intervallar structures pores : Completely porous
• Porosity type of vertical intervallar structures : ?
• Pores shape of vertical intervallar structures : Circular pores
• Building of tabulae : Independent from walls

Others informations

• Number of walls : 2
• Stratigraphical extension : Tommotian ; Atdabanian ; Botoman
• Geographical repartition : Mongolia ; Morocco ; Russia
• Shape of cup bulges : Both walls show folds
• Presence of chambers : None
• Type of habitus : Solitary ; Modular
• Structure of central Cavity (or internal if one wall) : Empty
• Presence of thorny corolla : None
• Russia : Altay Sayan ; Siberian Platform ; Transbaikal ; Tuva
• Botoman : 1
• Atdabanian : 1 ; 2 ; 3 ; 4
• Tommotian : 4
• General shape of folds affecting both walls : Transverse folds
• Type of modularity : Branching by longitudinal subdivisions ; Catenulate
• Shape of folds affecting both walls : Deep and close
• Cup shapes : Cylindrical-conical
• Type of other aquiferous unit : None

Systematic

• Orders : Ajacicyathida
• Superfamillies inside the Ajacicyathina : Bronchocyathoidea
• Famillies inside the Ajacicyathina : Ajacicyathidae
• Shape of carcass perforations openings (OW/SW) : Simple only
• Cup shapes : Cylindrical-conical
• Suborders inside the Ajacicyathida : Ajacicyathina

External view

• Cup shapes : Cylindrical-conical
• General shape of folds affecting both walls : Transverse folds
• Shape of folds affecting both walls : Deep and close
• Shape of cup bulges : Both walls show folds
• Structure of outer carcass wall (OW/SW) : Carcass wall well defined
• Type of modularity : Branching by longitudinal subdivisions ; Catenulate
• Type of habitus : Solitary ; Modular
• Size of carcass pores (OW/SW) : Uniform size
• Presence of carcass bumps: outer wall or single wall (OW/SW) : None
• Presence of carcass external plates: outer wall or single wall (OW/SW) : None
• Presence of carcass external plates: inner carcass wall (IW) : None (external plates and/or inner wall)
• Presence of thorny corolla : None
• Type of additional sheath (OW/SW) : None
• Type of additional sheath (IW) : None
• Repartition of carcass pores (OW/SW) : Homogeneous repartition
• Repartition types of carcass pores (OW/SW) : Straight rows of pores
• Shape of carcass perforations openings (OW/SW) : Simple only
• Presence of chambers : None
• Type of other aquiferous unit : None
• Subdivision of carcass perforations openings (OW/SW) : Without subdivision
• Number of walls : 2

Transverse section

• General shape of folds affecting both walls : Transverse folds
• Shape of folds affecting both walls : Deep and close
• Shape of cup bulges : Both walls show folds
• Structure of outer carcass wall (OW/SW) : Carcass wall well defined
• Structure of inner carcass wall (IW) : Carcass wall well defined
• Number of walls : 2
• Type of habitus : Solitary ; Modular
• Type of carcass perforations: outer wall or single wall (OW/SW) : Pores
• Presence of carcass bumps: outer wall or single wall (OW/SW) : None
• Building of carcass perforations (IW) : Without participation of vertical structures
• Type of carcass perforations: inner wall (IW) : Pores
• Structure of central Cavity (or internal if one wall) : Empty
• Type of vertical intervallar structures : Septa
• Presence of vertical intervallar structures : Present
• Presence of thorny corolla : None
• Type of links between intervallar structures : None
• Presence of intervallar cells : None
• Pores shape of tabulae : Pecten
• Presence of tabulae : Present ; none
• Type of other aquiferous unit : None
• Presence of carcass external plates: outer wall or single wall (OW/SW) : None
• Presence of carcass external plates: inner carcass wall (IW) : None (external plates and/or inner wall)
• Rows number of carcass perforations per intersept (OW/SW) : 2 AND more than 2 rows per intersept
• Rows number of carcass perforations per intersept (IW) : More than 2 rows per intersept only
• Porosity of vertical intervallar structures : Multiperforate

Longitudinal section

• General shape of folds affecting both walls : Transverse folds
• Shape of folds affecting both walls : Deep and close
• Shape of cup bulges : Both walls show folds
• Structure of outer carcass wall (OW/SW) : Carcass wall well defined
• Structure of inner carcass wall (IW) : Carcass wall well defined
• Number of walls : 2
• Type of modularity : Branching by longitudinal subdivisions ; Catenulate
• Type of habitus : Solitary ; Modular
• Type of carcass perforations: outer wall or single wall (OW/SW) : Pores
• Presence of carcass bumps: outer wall or single wall (OW/SW) : None
• Presence of carcass external plates: outer wall or single wall (OW/SW) : None
• Cup shapes : Cylindrical-conical
• Type of carcass perforations: inner wall (IW) : Pores
• Structure of central Cavity (or internal if one wall) : Empty
• Presence of carcass external plates: inner carcass wall (IW) : None (external plates and/or inner wall)
• Shape of morphological tubes (IW) : None
• Type of vertical intervallar structures : Septa
• Repartition of vertical intervallar structures pores : Completely porous
• Porosity type of vertical intervallar structures : ?
• Pores shape of vertical intervallar structures : Circular pores
• Presence of vertical intervallar structures : Present
• Presence of thorny corolla : None
• Type of links between intervallar structures : None
• Presence of intervallar cells : None
• Building of tabulae : Independent from walls
• Presence of tabulae : Present ; none
• Type of other aquiferous unit : None
• Presence of chambers : None
• Type of additional sheath (OW/SW) : None
• Type of additional sheath (IW) : None
• Presence of stipules (IW) : None
• Shape of morphological tubes (OW/SW) : None
• Rows number of carcass pores per intertabula (IW) : Several rows of pores between two successive tabulae only ; No tabula
• Porosity of vertical intervallar structures : Multiperforate
• Organization of tabulae inside the cup : Random

Oblique section

• General shape of folds affecting both walls : Transverse folds
• Shape of folds affecting both walls : Deep and close
• Shape of cup bulges : Both walls show folds
• Structure of outer carcass wall (OW/SW) : Carcass wall well defined
• Structure of inner carcass wall (IW) : Carcass wall well defined
• Number of walls : 2
• Type of habitus : Solitary ; Modular
• Size of carcass pores (OW/SW) : Uniform size
• Type of carcass perforations: outer wall or single wall (OW/SW) : Pores
• Presence of carcass bumps: outer wall or single wall (OW/SW) : None
• Presence of stipules (OW/SW) : None
• Shape of morphological tubes (OW/SW) : None
• Rows number of carcass pores per intertabula (IW) : Several rows of pores between two successive tabulae only ; No tabula
• Cup shapes : Cylindrical-conical
• Building of carcass perforations (IW) : Without participation of vertical structures
• Type of carcass perforations: inner wall (IW) : Pores
• Structure of central Cavity (or internal if one wall) : Empty
• Shape of morphological tubes (IW) : None
• Type of vertical intervallar structures : Septa
• Repartition of vertical intervallar structures pores : Completely porous
• Porosity type of vertical intervallar structures : ?
• Pores shape of vertical intervallar structures : Circular pores
• Presence of vertical intervallar structures : Present
• Presence of thorny corolla : None
• Presence of intervallar cells : None
• Building of tabulae : Independent from walls
• Pores shape of tabulae : Pecten
• Presence of tabulae : Present ; none
• Presence of chambers : None
• Type of other aquiferous unit : None
• Presence of carcass external plates: outer wall or single wall (OW/SW) : None
• Presence of carcass external plates: inner carcass wall (IW) : None (external plates and/or inner wall)
• Type of additional sheath (OW/SW) : None
• Type of additional sheath (IW) : None
• Presence of stipules (IW) : None
• Rows number of carcass perforations per intersept (OW/SW) : 2 AND more than 2 rows per intersept
• Rows number of carcass perforations per intersept (IW) : More than 2 rows per intersept only
• Shape of carcass perforations openings (IW) : Simple
• Porosity of vertical intervallar structures : Multiperforate
• Type of links between intervallar structures : None
• Organization of tabulae inside the cup : Random
• Shape of carcass perforations openings (OW/SW) : Simple only
• Subdivision of carcass perforations openings (OW/SW) : Without subdivision
• Subdivision of carcass perforations openings (IW) : Without subdivision

Tangential section

• Shape of carcass perforations openings (OW/SW) : Simple only
• Size of carcass pores (OW/SW) : Uniform size
• Repartition of carcass pores (OW/SW) : Homogeneous repartition
• Shape of carcass perforations openings (IW) : Simple
• Presence of thorny corolla : None
• Repartition of vertical intervallar structures pores : Completely porous
• Porosity type of vertical intervallar structures : ?
• Pores shape of vertical intervallar structures : Circular pores
• Pores shape of tabulae : Pecten
• Repartition types of carcass pores (OW/SW) : Straight rows of pores
• Subdivision of carcass perforations openings (OW/SW) : Without subdivision
• Subdivision of carcass perforations openings (IW) : Without subdivision

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Base mise à jour le 11 mars 2014 | Page générée avec Xper2 le 11 mars 2014