FW Ciliate 01

A large freshwater ciliate of some sort -- might be something Loxodes-like but I can't make out any gravity-sensing Müller's vesicles, and I think the shape is a little off. Ciliates are insanely diverse, and it's a bit overwhelming to learn to identify them... (edit: Litonotus sp.)

The two fairly large finely granular bodies are the somatic macronuclei. Ciliates carry two genomes: a transcriptionally silent one stored in the small micronuclei and a highly modified, polyploid transcriptionally-active variant stored in the much larger macronuclei. A pair of contractile vacuoles are also visible at opposite ends of the cell, as well as an algal prey in a digestive vacuole. Not sure what the random smaller vesicles and those long narrow inclusions are; the latter might be trichocysts or some weird bacteria, or perhaps none of the above. The mouth should be towards the right end of the cell (from our perspective).

Freshwater, Apr 2011, Vancouver

Category:

Science & Technology

Tags:

• protists
• ciliates
• microscopy

[PsiWavefunction]

Update: this ciliate is a Litonotus sp., a Haptorian ciliate closely related to Dileptus and Didinium – the long narrow things in the body are toxicysts which are a Haptorian synapomorphy, used to paralyse their prey (usually other ciliates). [h/t DH Lynn]