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Role in Cambrian

Genera: 308
Groups: 10
Descriptors: 122

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Matching terminologies





Last modified : 26 October 2012



Additional sheath: Second part of a wall composed by two zones (carcass + sheath).

Annulus (plur. annuli): Ring-shaped (annular) plate separating horizontal rows of pores.

Aquiferous unit: Part of the fossil corresponding to water-conducting system.

Astrorhiza: System of canals convergent on a single excurrent opening (osculum) of inner wall.

Attached: Microporous sheath attached directly to carcass pore lintels.

Bar: Radial-transverse lintel separating pores. It's biconcave in plan and with elongate cross-section.

Bract: Plate stems from lintels which incompletely covering a single pore.

Branching canal: Canal completely divided along the length into two subsidiary canals.

Bulges: External protuberances of the cup.

Bumps: Outer wall structure in shape of a subspherical/hemispherical dome.
Similar: Tumuli, pustula.

Calicle: Longitudinal tubelike intervallar structure, which can be hexagonal or tetragonal in cross-section.

Canal Zone A: Intervallum side.

Canal Zone B: Cavity central side.

Canal: Pore modified by skeletal structure thikening or by lintels streching. Canal length is greater than perforation diameter.

Carcass wall not well defined: syn. Rudimentary perforate wall.

Carcass: part of wall on intervallum side.

Catenulate: Chainlike modular organization consisting of individuals united laterally generated by incomplete longitudinal subdivision.

Central cavity Empty: Without any skeletal structure in the central cavity or in the inner cavity.

Central cavity Full: With secondary skeletal structures in central cavity or in inner cavity.

Central cavity Reduce: Due to the large development of the inner wall.

Central cavity: Inner space delimited by the inner wall of two-walled cup.
In one-walled cup = inner cavity.

Chamber: Space bounded by adjacent arched tabulae and their contiguous walls in a thalamid cup.

Chimneys: Small tubelike structure stems from outer wall's pores.
Syn.: Exaulos.

Clathri: Additional wall consisting of a layer of longitudinal ribs with or without transverse lintels.

Coarsely porous: Pore diameter greater than lintels width.

Completely porous: Pores distributed frequently and uniformly.

Corolla: Umbrella-like structure projecting from external surface of cup.

Cup: Calcareous archaeocyathan skeleton.

Cup: Conical: Cup in form of inverted cone.

Cup: Cylindrical: Conical cup nearly cylinder.

Cup: Discoid: Flat.

Cup: Domal: Cup in vault.

Cup: Subspherical: Cup nearly spherical.

Denticulate: With indented rims.

Dictyonal network: Three-dimensional intervallar structure composed by taeniae with tetragonal pores linked by synapticulae at each interpore.

Divided pore: Pores irregularly divided by radial protrusions of lintels.

Downwardly opening: Opening on intervallum side is higher than the other one.

External budding: Type of asexual reproduction, bud on outer wall of parent cup.

External plates: Plate covering incompletely one or several perforations of a wall.

Facet: Any face of a calicle or syrinx.

Finely porous: Pore diameter smaller than lintels width.

Fold: Succession of more or less regular annulations of both walls.

Fused: Adjacent bracts or scales of the same horizontal file are incompletely amalgamated to form a single structure covering two or more perforations of a wall.

Habitus: Pattern of living.

Horizontal opening: Opening on intervallum side is as high as the other one.

Independent: Microporous sheath supported by short beams arising from carcass pore lintels.

Inner wall: Internal part of the skeleton, separating central cavity and skeletal structures, composed by a porous carcass, simple or coated by an additional sheath.

Interparietal budding: Type of asexual reproduction, bud in intervallum.

Intersept: Part of a wall or intervallum between two adjacent radial vertical structures (septa, taeniae...).

Interseptal plate: Porous plate linking adjacent radial-longitudinal partitions (septa, taeniae, etc).
NB: Resembling flat synapticula.

Intervallar cell: Part of intervallum bounded by adjacent radial-longitudinal partitions and tangential synapticulae.

Intervallum: Space enclosed between the walls.

Inverted V-shaped: Resembles A in longitudinal section.

Irregular folds: Folds aren't periodic and synchronous. They can be transverse and/or longitudinal.

Irregular: No geometrical pattern.
syn. Basic, rudimentary.

Lintel: Skeletal structure separating and bounding adjacent pores or canals.

Longitudinal fold: Succession of more or less regular transverse annulations of cup.

Longitudinal plates: Resembling septa.

Longitudinal subdivisions: Type of asexual reproduction, bud in intervallum generated by complete longitudinal subdivision.

Massive pseudocolony: Modular organization in which no individual cup can be seen and generated by contiguous addition of new aquiferous units.

Mesh: Network composed by a layer of vertical elements linked or not by horizontal skeletal element.

Micropores: Small and simple perforation of microporous sheath or sieve.

Microporous sheath: Thin skeletal plate supported by carcass and pierced by micropores (lesser diameter than pores).

Modular: Primitive colony. Skeleton formed by several cups resulted of subdivisions.

Morphological tubes: Artificial groups corresponding to a same aspect in longitudinal section of different morphological structures.
i.e.: V-shaped = straight canal + bract or V-shaped canal morphological structures.

Multichambered: Cup incorporating two or more chambers.

Multiperforate: With several openings.

Non-branching canal: Canal not completely divided.

Non-porous: Canal lacking connecting pores or any other connection with adjacent canals.
syn.: Non-communicating.

Outer wall: External part of the skeleton, composed by a porous carcass, simple or coated by a additional sheath.

Pecten: Thin-tooth comb (with rods) structure.

Perforation: pores, canals or vertical tubes

Pillar: Longitudinal rodlike structure connecting adjacent tabulae.

Plate: Porous plate linking adjacent radial-longitudinal partitions (septa, taeniae, etc).
NB: Resembles a flat synapticula.

Plicate wall: Each intersept is individually folded formed sharp mid-interseptal longitudinal ridge.

Polygonal: Often = quadrate.
Similar: Cambroid type, anthoid type.

Pore: Simple perforation of any skeletal structure. Pore diameter is greater than thickness of the structure.

Pores 2 distinct sizes: Each group has the same size of pores.

Pores Irregular repartition: Pores covering partially the wall.

Pores Regular repartition: Pores covered the whole wall.

Pores Uniform size: All pores have got the same size.

Poretube: Structure of elongate, scooplike to tubular shape completely or almost completely covering a single pore.
NB: Poretubes resemble canals but have a bract origin.

Porous: Canal connected to its neighbors either by pores piercing mutual canal walls.
syn.: Simple communicating.

Protrusion: Rod divided pores.

Pseudoclathri: Beams arising from carcass pore lintels support a layer of longitudinal ribs and transverse lintels.

Pseudoseptum: Planar or slightly waved irregularly porous partition linking both walls of a two-walled cup with a radial-longitudinal distribution.

Pustula (plur. pustulae): Wall structure covering an individual pore and pierced by a single central orifice.
NB: Pustulae resemble simple tumuli.

Regular folds: Folds are periodic and synchronous.

Reticulate: Polygonal pores, the diameter of which is greater than lintel width.
syn. Netlike.

Scale: Plate incompletely covering two or more adjacent pores or intersepts in the same horizontal file. They are intermediate between fused bract and annulus.

Screen of planar rings: Successive horizontal annular shelves.

Septum (plur. septa): Planar porous partition linking both walls of a two-walled cup with a radial-longitudinal distribution.

Sieve: Aditional sheath stemmed from pores subdivisions.

Simple: Circular perforation.

Single wall: External part of the skeleton for one-walled cup, composed by a porous carcass, simple or coated by a additional sheath.

Single-chambered: Cup incorporating one chamber only.

Slitlike: Elongate elliptical shaped.

Solitary: Without subdivision or buds of the cup.

Sparsely porous: Rare pores irregularly distributed.

Spine: Skeletal structure comprising a narrow, elongate and typically tapering process with a circular to subcircular attachment area.
NB: Spines resemble bracts.

Spongiose: Massive inner wall consisting of elaborately waved, communicating canals.
syn.: Anastomosing communicating.

S-shaped: Resembles S in longitudinal section.

Stipule: Leaflike appendage arising from canal-bract junction in a wall of inverted-V or V-shaped appearance.

Stirrup: Perforation in front of each vertical intervalar structure. NB: Transverse section resembles stirrup.

Subdivided pore: Pores irregularly divided by radial protrusions of lintels.

Synapticula (plur. synapticulae): Narrow horizontal rod linking two adjacent vertical intervallar structures.

Syrinx (plur. syringes): Intervallar structure comprising porous radial horizontal or curved tube with hexagonal or tetragonal cross-section.

Tabella: Additional wall consisting of longitudinal ribs linked by transverse lintels.

Tabula (plur. tabulae): Transverse porous partition linking both walls of a two-walled cup.

Tabular plate: Incomplete tabula-like structure limited to several adjacent intersepta.

Taenia (plur. taeniae): Intervallar porous structure, non-planar, often dichotomous with a radial-longitudinal distribution.

Transverse fold: Succession of more or less regular longitudinal annulations of cup.

Tumulus (plur. tumuli): Outer wall structure in shape of a subspherical dome covering an individual and downwardly projected wall opening.

Upwardly opening: Opening on intervallum side is lower down than the other one.

Vertical intervallar structures: Longitudinal and often radial structures inside the intervallum (septa, taeniae...).

Vertical tube: One canal-like opening, longitudinally continuous along entire cup, bounded by longitudinal plates and lacking transverse partitions.

V-shaped: Resembles V in longitudinal section.

With participation of vertical intervallar structures: Formed by fluting of inner edge of septa.