Corallinales
-Heavily calcified thallus
-No apical depression
(as in things like Galaxaura, etc.)
What to look for…
•Thin (<5-10 cells thick) or thick crust?
•What does it look like in section?
-are any cell layers horizontally of vertically elongated?
-how thick (# of cell layers) is the “hypothallus” (the bottom
tissue layer) as compared to the “perithallus” (the middle
tissue layer)?
Non-articulated i.e. a crust
Is the thallus
Articulated
•Are there trichocytes (large cells that may produce surface
hairs) and if so are they scattered or in groups?
•Do conceptacles have a single or multiple pores?
•Are tetrasporangia zonately divided or cruciate?
•Is the thallus growing on another algae and which one?
•Is the crust growing from an originally 4-celled or
8-celled structure?
•Are segments uniform or variable in length?
•What is the branching pattern?
•What do the internodes look like in longitudinal section?
-are there multiple tiers of cells or only a single tier?
•Where are conceptacles found?
-apical segments, scattered, or at dichotomies?
Thin crust (<5-10 cells thick)
Titanoderma
vertically elongated cells
vertically elongated cells
lateral pit connections
lateral pit connections
Hydrolithon
Crust developing from
four-celled structure
horizontally elongated cells
Fosliella
Pneophyllum
Crust developing from
eight-celled structure
Only found growing
on Chamaedoris
Thick crust
Conceptacles with single pore
Hydrolithon
Lithophyllum
Neogoniolithon
Porolithon
Conceptacles with multiple pores
Lithothamnion
Mesophyllum
Sporolithon
Conceptacles with a single pore
Trichocytes absent
Lithophyllum
Trichocytes present
Trichocytes in horizontal groups
Porolithon
Trichocytes single and scattered
Multilayered “hypothallus”
Neogoniolithon
One cell thick “hypothallus”
Distinct, one cell thick “hypothallus”
Hydrolithon
Conceptacles with multiple pores
Tetrasporangia cruciate;
Multichambered sori
Sporolithon
cruciate tetrasporangia
multichambered sori
Tetrasporangia zonate;
Multichambered sori?
Dimerous thallus construction
Lithothamnion
Dimerous construction
Tetrasporangia zonate;
Single-chambered conceptacles;
Monomerous thallus construction
zonate tetrasporangia
Mesophyllum
Monomerous construction, “coaxial”
Articulated
variable length medullary cells
Unequal segments;
Variable length medullary cells;
Multi-tiered genicula;
Scattered conceptacles
Amphiroa
multiple tiers of cells
in genicula
unequal intergenicula segments
conceptacles scattered
Articulated
Segments nearly equal;
Medullary cells of equal length;
Single-tiered genicula;
Conceptacles in swollen segments
that will form branches;
Branching dichotomous
dichotomous branching
Jania
Segments nearly equal;
Medullary cells of equal length;
Single-tiered genicula;
Conceptacles in swollen apical
segments that may have projections;
Branching mostly pinnate
Haliptilon
pinnate branching
conceptacles forming
branches
single tier of cells
in genicula
single tier of cells
in genicula