Trachelomonas raciborskii var. nova

(Dreżepolski, 1925)

Most likely ID: n.a.


Synonym: n.a.


Sampling location: Simmelried


Phylogenetic tree: Trachelomonas raciborskii var. nova



  • lorica broadly ellipsoidal
  • apical pore without collar
  • length 41 µm, width 33 µm
  • lorica covered with spines of equal length in apical fourth
  • lorica brownish or orange
  • eyespot large
  • chloroplasts disc-shaped without pyrenoid
  • flagellum about body length
Trachelomonas raciborskii var. nova

So far I have found Trachelomonas raciborskii var. nova only once in January 2022 in the Simmelried. The species is easy to identify because it only has spines in the anterior fourth of the lorica. The spine are are quite short and all of the same length. The rest of the lorica has only fine pores but no other spines. In addition, Trachelomonas raciborskii var. nova is quite large with a length of over 40 µm.


The description of Dreżepolski is very short. The eyespot and chloroplasts are not mentioned. I could observe in my specimens that the eyespot is quite large and the chloroplasts are disc-shaped without pyrenoids (s. fig. 1 c). The number of chloroplasts is 25–30. Dreżepolski also does not describe the flagellum, which in my specimens was somewhat as long as the body.


Fig. 1 a-c: Trachelomonas raciborskii var. nova. L = 48 µm. Three focal planes of a freely swimming specimen. Note the short spines (AS) covering the apical fourth of the lorica. The chloroplasts (Chl) are disc-shaped without pyrenoid. ES = eyespot, F = flagellum, Nu = nucleus. Obj. 100 X.