Genus: Cell body flat, large, variable in shape, longer than wide; strong constriction at center; each semicell with several notches; cell wall with many short spines (Illustrations of The Japanese Fresh-water Algae, 1977).
Species [ var. thomasiana ]: Cell body 95-98 μm long, 97-98 μm wide, isthmus 22-23 μm wide,
Google Image Search
Conspicuous protrusions present at the center of the cell
v. thomasiana
223 x 190 μm
Sukawa highland
Kurikoma mountain
Akita, 2005
v. javanica
μm
Miyatoko m.4
Minami-Aizu
Fukushima, 2008
v. javanica
μm
Miyatoko m.6
Minami-Aizu
Fukushima, 2008
v. javanica
μm
Kareki-numa
Nikko
Tochigi, 2008.8
v. javanica
μm
Kareki-numa
Nikko
Tochigi, 2008.9
v. pulcherrima
220 x 185 μm
Kakuman-buchi
Akagi mountain
Gunma, 2005Conspicuous protrusions absent at the center of the cell; similar to M. denticulata v. javanica
v. notata
225 x 205 μm
Tashirodaira
Hakkoda mountain
Aomori, 2006
v. notata
225 x 180 μm
Igashira park
Mooka
Tochigi, 2006
v. notata
284 x 262 μm
Ichinose-enchi
Norikura highland
Nagano, 2006
v. notata
μm
Dojo-ike
Norikura highland
Nagano, 2007
v. notata
240 x 205 μm
Kowashimizu
Suwa
Nagano, 2007
v. notata
μm
Yamakado marsh
Nishi-Asai
Shiga, 2008
v. notata
μm
Kashibaru m.2-2
Karatsu
Saga, 2008
v. notata
μm
Kashibaru m.II
Karatsu
Saga, 2008