Descripteur : Type of carcass external plates (IW)
Type du descripteur : categorical
External plates: Plate covering incompletely one or several perforations of a wall.
Carcass: Part of wall on intervallum side.
IW: Inner wall.
- Spines
-
Spine: Skeletal structure comprising a narrow, elongate and typically tapering process with a circular to subcircular attachment area.
NB: Spines resemble bracts.
Spines
- Bracts
-
Bract: Plate stems from lintels which incompletely covering a single pore.
Lintel: Skeletal structure separating and bounding adjacent pores/canals. - Bracts AND fused bracts
-
Bracts and structures similar to scales coexist.
Bract: Plate stems from lintels which incompletely covering a single pore.
Lintel: Skeletal structure separating and bounding adjacent pores/canals.
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.
NB: fused bracts resemble scales. - Bracts AND annuli
-
Bract: Plate stems from lintels which incompletely covering a single pore.
Lintel: Skeletal structure separating and bounding adjacent pores/canals.
Annulus (plur. annuli): Ring-shaped (annular) plate separating horizontal rows of pores. - Scales
-
Scale: Plate incompletely covering two or more adjacent pores or intersepts in the same horizontal file. They are intermediate between fused bract and annulus.
Scales
- Scales AND fused scales
-
Scales and structures similar to annuli coexist.
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.
NB: fused scales resemble annuli - Annuli
-
Annulus (plur. annuli): Ring-shaped (annular) plate separating horizontal rows of pores.
Annuli
Annuli
- Annuli AND fused annuli
-
Annuli of different horizontal files may mutually coalesce.
- Poretubes
-
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.
Hiérarchie
Presence of carcass external plates: inner carcass wall (IW) | |_ Type of carcass external plates (IW) | |_ Localization of carcass bracts (IW) {Spines , Scales , Scales AND fused scales , Annuli , Annuli AND fused annuli , Poretubes} | |_ Shape of the interlocking of successive carcass annuli (IW) {Spines , Bracts , Bracts AND fused bracts , Scales , Poretubes} | |_ Localization of carcass annuli according tabulae (IW) {Spines , Bracts , Bracts AND fused bracts , Scales , Poretubes}