Genus: Highly flattened; pellicle firm; body form constant (Kudo, 1966). Chloroplasts small, discoid, pyrenoids usually absent; most species flat and leaf-shaped; often with ridges or fins running helically or longitudinally (Illustrated Guide, 1985).
Species: 120-170 μm long, 45-70 μm wide; usually slightly twisted; a long caudal prolongation; flagellum about 1/2 body length; stigma prominent; a discoidal paramylon (paramylum) body central; pellicle longitudinally striated (Kudo, 1966).
var. longicauda: cell body 85-170 μm long, 45-70 μm wide; locomotive flagellum shorter than the cell body; a single paramylon body ring shaped (An Illustrated Guide to Freshwater Zooplankton in Japan, 2000).
Google Image Search
Tail long ![]()
P. longicauda
body, 90 x 56 μm
tail, 60 μm
near Mihashi Park
Saitama, 2006![]()
P. longicauda
body, 84 x 58 μm
tail, 77 μm
Japan, 199?![]()
P. longicauda
body, 75 μm
tail, 65 μm
Sakitama-kofun p.
Gyoda
Saitama, 2004![]()
P. longicauda
body, 73 μm
tail, 71 μm
Uruguay, 1999![]()
P. longicauda
body, 70 μm
tail, 77 μm
near Town Hall
Shobu
Saitama, 2004![]()
P. longicauda
body, 155 μm
tail, 70 μm
Iyari marsh
Omachi
Nagano, 2007![]()
P. longicauda
body, 64 μm
tail, 71 μm
Uruguay, 1999![]()
P. longicauda
body, μm
tail, μm
Japan, 199?![]()
P. longicauda
body, 61 μm
tail, 48 μm
Takasaka
Saitama, 2002![]()
P. longicauda
body, μm
tail, μm
Iruma
Saitama, 2003![]()
P. longicauda
body, 48 μm
tail, 50 μm
water reservoir
near Yamaguchi Univ.
Yamaguchi, 2004![]()
P. longicauda
body, 50 μm
tail, 30 μm
Izumo Shrine
Izumo
Shimane, 2006![]()
P. longicauda
body, μm
tail, μm
Nogyo Fureai p.
Toride
Ibaraki, 2008Tail short ![]()
P. longicauda, x 400
body, 81 x 60 μm
tail, 61 μm
Japan, 199?![]()
P. longicauda, x 400
body, 80 x 50 μm
tail, 48 μm
Japan, 199?![]()
P. longicauda ?
body, 55 μm
Mihashi Park
Saitama, 2002Cell body elongated ![]()
P. longicauda
body, 84 x 59 μm
tail, 60 μm
Saitama, 1999