Extended Observation Description on Melosira lineata
Melosira lineata (Roth) Guiry 2019
Morphological Details of Melosira lineata
The species is characterized by cylindrical to subspherical cell shape. The cell groups form filaments that are held together by mucilaginous pads. The cells characteristically associate in groups of two or three and are connected by mantle structures called “cingula”.

Fig. 1: Filament of Melosira lineata. Two groups of 3 cells each. Scale bar indicates 25 µm (right).
Sampling location: Baltic Sea, Kieler Förde, Kiel Fjord (Germany), Latitude: 54.3894126, Longitude: 10.1749055

Fig. 2: Upper left inset: The focal plane is at the chloroplasts, which line the frustule lying parietal (arrow). Groups of 2 cells each. Scale bar indicates 50 µm.
Main image: The cingula (double arrowhead) forming a cylindrical mantle connect two or three cells. These coats enclose the valves of the individual cells. The ornamentation of the cingula differs significantly from that of the valves (double headed arrow). Scale bar of main image indicates 25 µm.
The sexual reproduction of Melosira lineata
The sexual reproduction of centric diatoms (Centrales) is characterized by oogamy. In Melosira, the spermatozoids are formed in narrower, the oogonia in broader filaments. After meiosis, four mobile spermatozoa with one flagellum develop in the male gamete mother cells (antheridia), in each of the oogonia three meiotic nuclei collapse and only one egg cell capable of fertilization remains.
(After Krammer, K. and van den Hoek, C.)

Fig. 3: Spermatozoids: We can see flagella (arrow) and their golden-brown chloroplast (double arrowhead, color due to the accessory dye fucoxanthin) at the posterior end of each spermatozoid (arrowhead).
Scale bar indicates 50 µm.
© Wolfgang Bettighofer,
images under Creative Commons License V 3.0 (CC BY-NC-SA).
For permission to use of (high resolution) images please contact postmaster@protisten.de.
New items
crassa
digitus
var. lamellosum
digitus
var. latum
oblongum
interruptum
spec.
spec.
kinahanii
spec.
polymorphum
var. polymorphum
spec.
spirostriolatum
digitus
brebissonii
rotata
swartzii
capitulum
antilopaeum
neosinuosum
brebissonii
pachydermum
thomasiana
var. notata
ansatum
forficulatum
var. verrucosum
neodepressum
armatum
oblongum
porteanum
truncata
rhomboidale
furcatum
uncinatum
dissiliens
pseudonitidulum
var. validum
truncata
var. bahusiensis
bidentatum
hirsutum
cucurbitinum
minor
pyramidatum
truncata
var. quadrata
binale
var. gutwinskii
inconspicuum
borreri
americana
quadratulum
trabecula
var. elongatum
coeseli
margaritacaeum
bicuneatum
apiculata
simplicius
crenulatum
crassum
simonyi
var. sparsiaculeatum
caelatum
crux-melitensis
sparsepunctatum
ehrenbergii
didelta
spongiosum
var. perbifidum
connatum
denticulata
subarctoum
trabecula
var. trabecula
humerosum
teliferum
dejectus
spec.
conspersum
komarekii
papillifera
arboricola
venustum
var. excavatum
viridis
pulchellum
tripus
granulatus
var. granulatus
subspicatus
humerosum
var. affine
nostochinearum
convergens
arcuata
integrum
aureus
rotata
lunaris
grevillei
lunatus
alternans
irregularis
laevis
var. laevis
ehrenbergianum
luetkemuelleri
var. carniolicum
reticulatum
tetras
limneticum
viridis
cystozygote
tetrachotoma
simplex
var. sturmii
biradiatum
microporum
var. octaedricum
braunii
reinhardtii
pusillum
lacustris
speculum
diaphanum
New items
crassa
digitus
var. lamellosum
digitus
var. latum
oblongum
interruptum
spec.
spec.
kinahanii
spec.
polymorphum
var. polymorphum
spec.
spirostriolatum
digitus
brebissonii
rotata
swartzii
capitulum
antilopaeum
neosinuosum
brebissonii
pachydermum
thomasiana
var. notata
ansatum
forficulatum
var. verrucosum
neodepressum
armatum
oblongum
porteanum
truncata
rhomboidale
furcatum
uncinatum
dissiliens
pseudonitidulum
var. validum
truncata
var. bahusiensis
bidentatum
hirsutum
cucurbitinum
minor
pyramidatum
truncata
var. quadrata
binale
var. gutwinskii
inconspicuum
borreri
americana
quadratulum
trabecula
var. elongatum
coeseli
margaritacaeum
bicuneatum
apiculata
simplicius
crenulatum
crassum
simonyi
var. sparsiaculeatum
caelatum
crux-melitensis
sparsepunctatum
ehrenbergii
didelta
spongiosum
var. perbifidum
connatum
denticulata
subarctoum
trabecula
var. trabecula
humerosum
teliferum
dejectus
spec.
conspersum
komarekii
papillifera
arboricola
venustum
var. excavatum
viridis
pulchellum
tripus
granulatus
var. granulatus
subspicatus
humerosum
var. affine
nostochinearum
convergens
arcuata
integrum
aureus
rotata
lunaris
grevillei
lunatus
alternans
irregularis
laevis
var. laevis
ehrenbergianum
luetkemuelleri
var. carniolicum
reticulatum
tetras
limneticum
viridis
cystozygote
tetrachotoma
simplex
var. sturmii
biradiatum
microporum
var. octaedricum
braunii
reinhardtii
pusillum
lacustris
speculum
diaphanum