Dileptus sp.

[75RR]

Neofluar 25x/0.60, DIC (40x slider), 210µm length, fresh water, Olympus E-P2

It is curious to see just how much the Dileptus' probosis is like an elephant's trunk.

The mouth is also at the base of its 'trunk'

Sampling of the freshwater samples continues

[Wes]

Very nice! Thanks for sharing.

So the proboscis acts like a hunting spear to bring an unsuspecting protozoan to a violent end?

[75RR]

Thanks Wes

I was referring to the trunk's movement, which seemed elephant like to me anyway. In this case the 'trunk' does not pick things up or grab but stuns its prey. Think taser.

"Species of Dileptus occur in fresh and salt water, as well as mosses and soils. Most are aggressive predators equipped with long, mobile proboscides lined with toxic extrusomes, with which they stun smaller organisms before consuming them."

https://en.wikipedia.org/wiki/Dileptus

[Bruce Taylor]

Very nice find! This guy is in the order Dileptida, but in a different family. Dileptus has small, scattered macronuclei, whereas your organism has a large, conspicuously tubular macronucleus. It seems to be a dimacrocaryonid (Monomacrocaryon, Dimacrocaryon or Rimaleptus). The exact shape of the macronucleus isn't obvious, so I can't suggest a genus-level ID.

[75RR]

Very nice find! This guy is in the order Dileptida, but in a different family. Dileptus has small, scattered macronuclei, whereas your organism has a large, conspicuously tubular macronucleus. It seems to be a dimacrocaryonid (Monomacrocaryon, Dimacrocaryon or Rimaleptus). The exact shape of the macronucleus isn't obvious, so I can't suggest a genus-level ID.

Many thanks for the added accuracy in the ID

I should remember to qualify my tentative efforts as Possibly so and so ... :)