Cryptaulax thiophila (Skuja, 1956)

Most likely ID: n.a.


Synonym: n.a.


Sampling location: Simmelried


Phylogenetic tree: Cryptaulax thiophila



  • body cylindrical ellipsoidal, with a distinct spirally groove
  • strong metabolic movement
  • length 16–31 µm
  • two long flagella (locomotion and trailing) of almost equal length
  • periplast smooth
  • apical end extended to a rostrum
  • nucleus located centrally
  • short gullet subapical with associated contractile vacuole
Cryptaulax thiophila

I regularly find Cryptaulax thiophila in the anaerobic siltation zone of the Simmelried. The specimens are usually found between colonies of rhodobacteria. I have not yet been able to find this species in my other sampling sites.


Cryptaulax thiophila is comparatively easy to identify by the two very long and thick flagella and the spiral groove that runs to the posterior end of the body. The flagellate is very metabolic. Nevertheless, the groove is always visible. According to Skuja (1956), however, the groove disappears in fully eaten specimens. It therefore appears to be a kind of “expansion groove”.


Fig. 1 a-f: Cryptaulax thiophila. L = 18 µm. A specimen during the metobolic movement. Note the apical rostrum (arrow, b) and the spirally groove (SGR, e) running to the posterior end. CV = contractile vacuole, F1, F2 = flagella, Nu = nucleus. Obj. 100 X