20
carolinea, 68
(2010)
Table 1. Comparing determination-relevant taxonomic features of similar Phormidium species inclusive Leptolyngbya vandenberghenii.
Features
“
Phormidium
Phormidium
Phormidium
Phormidium
Phormidium
spec.”
corium
inundatum
taylori
rimosum
Width of filaments µm
3,5 – 4,5
? – 3,7
Width of trichomes µm
2,9 – 3,7
3 – 5,4
3 – 5
4 – 7
2,6 – 3,2
Cell geometry
isodiametric
isodiametric -
isodiametric,
isodiametric
mostly shorter
longer than wide
shorter or lon-
(
little shorter
than wide
ger than wide
than wide)
Cell-length µm
3,5 – 5
3,4 – 6,4
3,3 – 8
2 – 7
1,4 – 3 (4,2)
Constrictions at the cross walls
no
no
no
no (-little)
no or little
Granulated at the cross walls
no or little
no
yes
no
no
Filament orientation
straight, stiff,
long, curved,
± straight, en-
long, parallel
parallel –
parallel
intertwined
tangled
± entangled
intertwined
Ending of trichome
straight, not
straight, not
briefly atte-
straight, briefly
not attenua-
attenuated
attenuated
nuated
attenuated
ted
Apical cell
rounded, ob-
rounded, ob-
conical roun-
broad roun-
broad roun-
tuse conical
tuse conical
ded
ded
ded
Calyptra
no
no
no
?
no
Sheaths
thin, firm, co-
thin, firm, colour-
thin, mucila-
thin, stiff, co-
thick, colour-
lourless, not
less, not lamell-
ginous
lourless
less
lamellated
ated
Stainable with chlor.-zinc-jod ?
no
yes
yes
?
?
Carbonate encrusting?
no
no
no
no
?
Carbonate boring?
yes
?
no
?
?
Form of thallus
brushlike within
leathery-mem-
membrana-
?
thin, partly
the rock matrix
branaceous,
ceous
chasmolithic
substrate covering
