Family: Peristomal disc lacks stalk; body on aboral stalk; if stalkless, in lorica; solitary (Illustrated Guide, 1985).
Genus: Similar to Epistylis; but solitary with a non-contractile stalk; numerous species (Kudo, 1966).
->> Description at WPRNO Google Image Search
O. annulata
31 x 16 μm
Japan, 1998
O. annulata
34 x 16 μm
Toneri Park
Tokyo, 2001
O. annulata
29 x 15 μm
Minuma-no-numa
Omiya daisan p.
Saitama, 2005
O. similis
32 x 20 μm
Saitama, 1999
O. pusilla
27 x 17 μm
Koshigaya
Saitama, 2001
Opisthostyla sp.
38 x 18 μm
Hirose athletic p.
Kumagaya
Saitama, 2004
Opisthostyla sp.
μm
Ryugahara marsh
Yuri-Honjo
Akita, 2008
Opisthostyla sp.
μm
Fujimitashiro
Katashina
Gunma, 2007
Similar genus --> > Rhabdostyla
