[1] Dileptus margaritifer has a slender body, usually about 450 μm in length and very flexible, narrowing at the posterior into a small, sharp tail.

At its front, it has a broad and tapering proboscis, reminiscent of an elephant's trunk in its shape and flexibility, but with a flattened rather than round cross-section.

The cell has a row of 4-20 contractile vacuoles along the dorsal surface, and at least 200 macronuclei scattered in the cytoplasm, with several spherical micronuclei distributed among them.

Dileptus margaritifer feeds upon other unicellular organisms, using toxic extrusomes embedded in its proboscis to strike and stun its prey.

Division may be preceded by conjugation, a sexual phenomenon in which two ciliates of compatible mating types exchange genetic material by reciprocal transfer of haploid gametes, derived by meiosis from each cell's micronuclei.