By earlier authors Dexiotrichides centralis is described as a very common species, especially in nutrient-rich waters. However, this ciliate was described by Foissner, Berger and Kohmann in 1994 in their “Revision der Ciliaten des Saprobiensystems, Band II” (s. literature) and it was stated: “wir haben diese Art noch nie gesehen! (However, we have never seen this species!)”. In fact, I have also been able to find only 4 specimens of Dexiotrichides centralis in my sampling sites within 25 years. It remains unclear whether the species has become generally rarer in the last 100 years or whether the wrong finding areas were sampled.

Based on these 4 specimens I could document the main characteristics of Dexiotrichides centralis. In my population, all specimens had a very long caudal cilium (about body length, s. fig. 1a). In addition, all specimens contained very large, 7–8 µm long, symbiotic bacteria (s. fig. 3b and 4). They must be symbiotic bacteria, because I could find food vacuoles co-occuring with these bacteria in the cytoplasm (s. fig. 4). Thus, the 7–8 µm long bacteria were not ingested as food. As described by Schmaller from protargol preparations (s. drawing above), the micronucleus is located in the anterior fifth of the cell and is hard to find (s. fig. 5). On the left side a small field of basal bodies without cilia is located below the mouth opening. This is probably the so-called scutica (s fig. 3a). From this field of basal bodies the oral apparatuses of the two daughter cells are organized during cell division. On the right side of the body I could observe an oblique cilia-free zone as drawn by Kahl (s. drawing above and fig. 6).