Ciliates

Other free-swimming ciliates

Colpoda, Litonotus, Frontonia, Loxophyllum, Dileptus, Loxodes and many more

Ciliates come in hundreds of freshwater genera. If yours is none of the classic shapes in the key, it probably belongs here.

Dileptus sp.. Video: Deuterostome, CC BY-SA 3.0, via Wikimedia Commons.

What to look for

  • A single cell with cilia, a mouth area and food vacuoles inside; no jaw, no gut.
  • Shape and the arrangement of cilia around the mouth are what specialists use: a long proboscis (Dileptus), a flat knife-like body (Litonotus), a small sphere that jumps (Halteria).
  • Naming to genus usually needs 400× and a ciliate guide; the clips on this page show some common ones.

Size in the field

Anything from a tiny dot at 100× to a fifth of the field.

Where to find it

Every pond sample, hay infusion and aquarium filter.

Clips 14

0:25Dileptus sp.Other free-swimming ciliates 0:20Dileptus 1Other free-swimming ciliates 0:08Colpoda swimming at 100×Other free-swimming ciliates 0:11Colpoda stuckOther free-swimming ciliates 0:20Colpoda spiralis at 400×Other free-swimming ciliates 0:34Colpoda spiralisOther free-swimming ciliates 0:10Colpoda pair 2Other free-swimming ciliates 0:10Colpoda pair 1Other free-swimming ciliates 0:14Colpoda in detail at 400× 2Other free-swimming ciliates 0:15Colpoda in detail at 400× 1Other free-swimming ciliates 0:16Colpoda circling at 100×Other free-swimming ciliates 0:10Colpoda at 400×Other free-swimming ciliates 0:25Climacostomum virens feedingOther free-swimming ciliates 0:24Big Colpoda at 100×Other free-swimming ciliates