B
ackhaus
:
Phormidium ingrediens sp. nova
21
Contin. Tab. 1.
Features
Phormidium
Phormidium
Phormidium
Leptolyngbya
incrustatum
toficola
umbilicatum
vandenberghenii
Width of filaments µm
–
–
–
(2,5) 3,5 – 4
Width of trichomes µm
(3) 4 – 6,5
3 – 4,5
3 – 4,5
3 – 4,8
Cell geometry
shorter than wide
isodiametric
isodiametric -
(
isodiametric) –
(1/3
of cell-length)
shorter than wide
longer than wide
Cell-length µm
2,3 – 5,6
2,3 – 5
3 – 5
2,5 – 4 (-5)
Constrictions at the cross walls
no (- little)
no
no
no (– little)
Granulated at the cross walls
no
–
no
?
Filament orientation
straight – entangled
entangled
curved – parallel
straight, ± curved
Ending of trichome
straight, briefly
straight, briefly
straight, briefly
straight, briefly
attenuated
attenuated
attenuated
attenuated
Apical cell
hemispherical –
obtuse – conical
obtuse – conical
rounded
conical rounded
Calyptra
?
no
no
no
Sheaths
thin, mucilaginous
very thick, muci-
thick, diffluent
firm, colourless
–
lamellated (yelloish)
lagineous – la-
mellated
Stainable with chlor.-zinc-iod.
no
no
yes
no
Ca-carbonate encrusting?
yes, very hard
yes, hard, petrified
yes, stony
yes
Carbonate boring?
(
yes)
?
?
no
Form of thallus
wart-like
spread (?)
wart-like
spread
