A ciliate from a paddy field

After being collected from a paddy field, the sample was put on DNB agar plate (diluted nutrient broth with agar) with a drop of distilled water for 4 days, and then observed. A ciliate is busily swimming in various directions, making sharp turns and suddenly reversing course.

Commentary by Prof. Yuji Tsukii, Hosei University
This ciliate belongs to order Stichotrichida.

http://protist.i.hosei.ac.jp/taxono.....

A variety of ciliates are included in this group. To identify them to the species level, it is necessary to stain the cirri by a special technique and to observe the number and arrangement of the cirri. Since we cannot see any cirri on the ciliate in this video, we cannot determine even which genus it is.

However, when the organism changes direction, it also changes the body shape itself. Therefore this organism is certainly not a member of genus Stylonychia in Sporadotrichina, Oxytrichidae group.

Organisms belonging to genus Oxytricha or genus Urostyla change directions in a similar manner to the organism in this video.

Sampling Date : 22 September 2006

Sampling Site : KASHIMADAI paddy field  Google Map