Long, narrow ciliates from a paddy field

After being collected from a paddy field, the sample was put on 1% agar plate with a drop of distilled water and kept for a few days.

Two long, narrow ciliates are moving back and forth as if they were synchronized.

Commentary by Prof. Yuji Tsukii, Hosei University
This ciliate is probably Spirostomum intermedium, within the genus Spirotomum, which includes species of several sizes. The reasons for classifying it as S. intermedium include its size (500μm), and the location of the cytostome (mouth) near the center. However, other typical identifying features are missing in this video. We cannot see the macronuclei connected like a string of beads, nor can we clearly distinguish the nuclei from food vacuoles. If this ciliate has only one large macronucleus, it might be a larger variety of S.teres, which is usually 300 to 400μm long and has one large macronucleus in the middle of a slender body. So based on size, this ciliate is more likely S. intermedium.

http://protist.i.hosei.ac.jp/PDB/Im.....

Sampling Date : 16 October 2006

Sampling Site : KASHIMADAI paddy field  Google Map