|   P. viridis
 155 x 27 μm
 Nidanuma
 Tsuchiyu-onsen
 Fukushima, 2005
 |   P. viridis
 152 x 27 μm
 Kannon-numa
 Shimogo
 Fukushima, 2005
 |   P. viridis
 145 x 25 μm
 Tanohara marsh
 Shiga highland
 Nagano, 2004
 |   P. viridis
 141 x 26 μm
 Lake Nojiri
 Shinano
 Nagano, 2004
 | 
|   P. viridis
 - Valve view -
 140 x 25 μm
 Senjo-ga-hara
 Nikko
 Tochigi, 2003
 |   P. viridis
 138 x 23 μm
 Tashirodaira m.
 Hakkoda mountain
 Aomori, 2005
 |   P. viridis
 - Valve view -
 130 x 24 μm
 Hidaka
 Saitama, 2003
 |   P. viridis
 125 x 22 μm
 Iroha-numa
 Zao mountain
 Yamagata, 2005
 | 
|   P. viridis
 or P. maior ?
 123 x 22 μm
 Koigakubo marsh
 Tessei-cho
 Okayama, 2004
 |   P. viridis
 or P. maior ?
 122 x 21 μm
 near Town Hall
 Shobu
 Saitama, 2005
 |   P. viridis
 or P. semicruciata ?
 99,120 x 21 μm
 Hakama marsh
 Madarao highland
 Niigata, 2005
 |   P. viridis
 or P. maior ?
 100 x 21 μm
 Demaru-nakago
 Kawajima
 Saitama, 2005
 | 
|   P. viridis
 104-114 x μm
 Watarase Wetland
 Fujioka
 Tochigi, 2005
 |   P. viridis
 μm
 Japan, 1997
 |   P. viridis
 - Valve view -
 109 x 24 μm
 Hidaka
 Saitama, 2003
 |   P. viridis x 400
 - Valve view -
 106 x 19 μm
 Japan, 1998
 | 
|   P. viridis
 104 x 21 μm
 Shimizu-daira
 Nasu
 Tochigi, 2005
 |   P. viridis
 103 x 25 μm
 Kisuge konuma
 Shimogo
 Fukushima, 2005
 |   P. viridis
 102 x 18 μm
 Daidarabotchi-ike
 Iizuna-kogen
 Nagano, 2003
 |   P. viridis ?
 101 x 19 μm
 Senjo-ga-hara
 Nikko
 Tochigi, 2003
 | 
|   P. viridis
 90 x 18 μm
 Nidanuma
 Tsuchiyu-onsen
 Fukushima, 2005
 |   P. viridis
 μm
 Japan, 1997
 |   P. viridis
 89 x 18 μm
 Japan, 1998
 | 
|   P. viridis
 88 x 19 μm
 Hitotsugi
 Yoshimi
 Saitama, 2004
 |   P. viridis
 82 x 17 μm
 Numa-no-hara m.
 Madarao highland
 Niigata, 2005
 |   P. viridis ?
 or P. gibba ?
 78 x 15 μm
 Shin-Akitsu
 Higashi-Murayama
 Tokyo, 2004
 |   P. viridis ?
 95 x 19 μm
 Ichinose-enchi
 Norikura highland
 Nagano, 2005
 | 
|   P. viridis ?
 170 x 28 μm
 Shijuhachi-ike
 Shiga highland
 Nagano, 2005
 |   P. viridis ?
 46 x ? μm
 Japan, 1998
 |   P. viridis ?
 - Valve view -
 69 x 24 μm
 Uruguay, 1999
 |