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License How to cite ARCHAEOCYATHA Role in Cambrian Morphology Bibliography KNOWLEDGE-BASE Genera: 308 Groups: 10 Descriptors: 122 Properties INTERACTIVE KEY User guide Matching terminologies Glossary PUBLISHED KNOWLEDGE-BASE CONTRIBUTORS CONTACT Visitors: Last modified : 26 October 2012 |
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- ARCHAEOCYATHA - Glossary | |
GlossaryAdditional 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. |
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