I do find Lacrymaria olor at many of my sampling sites, but mostly only single specimens. In my experience, the species seems to be more often found among dead aquatic plants floating on the surface.

The most characteristic feature of Lacrymaria olor is the high contractility and mobility of this species. This especially concerns the neck, which can stretch up to 800 µm in length. Although the neck becomes very thin in the process, it is extremely flexible and mobile. It often bends at angles but can also bend almost circularly (s. fig. 2 a-b). The head, armed with extrusomes, performs very fast, searching, and tactile movements.

Lacrymaria olor differs from the numerous other species within the genus Lacrymaria by the two macronuclei and two contractile vacuoles. The two macronuclei are located approximately in the middle of the body. Between them lies a small micronucleus (s. figs. 5 b and 8). Of the two contractile vacuoles, one is subterminal at the posterior end while the second is found in the anterior third of the body (s. fig. 5 a).

The longitudinal rows of cilia run counterclockwise over the body (s. fig. 6). Between the rows of cilia are rows of granules. Spiral rows of elongated cilia are also present on the head (s. fig. 7 b). These form an apical tuft of cilia that protrudes beyond the apical end of the head. In the head of Lacrymaria olor, there are 2 types of extrusomes, which are also distributed in the cytoplasm. Type 1 extrusomes are slightly curved rods with a length of 11–12 µm, and type 2 are very short, very slightly curved rods with a length of 2–3 µm (s. figs. 7 a and 9).