Coleps hirtus (Nitzsch, 1817)

Most likely ID: n.a.

 

Synonym: n.a.

 

Sampling location: Simmelried, Purren pond, Mainau pond, Bussenried, Bündtlisried, Ulmisried, Mühlhalden pond

 

Phylogenetic tree: Coleps hirtus

 

Diagnosis: 

  • length 40–65 µm
  • cell barrel-shaped
  • CV terminal
  • uniform ciliation
  • 15–20 longitudinal rows of plates
  • one caudal cilium
  • macronucleus spherical
  • apical mouth opening with basket
  • three spines at posterior end
  • shape of the “windows” in the carapace are pretzel-shaped
Coleps-hirtus
Coleps hirtus

Coleps hirtus is one of the most common ciliates ever. I find it throughout the year in all my localities. With low magnifications (< Obj. 40X) the identification can be difficult. Confusion with other Coleps species is then not impossible. Therefore you have to look closely at the fielding of the carapace with the 100 X objective. Coleps hirtus has clearly pretzel-shaped windows in the carapace. Also, the number of caudalcilia should be checked in any case. There should be only one caudal cilium.

Fig. 1 a-c: Coleps hirtus. L = 67 µm. A freely swimming specimen. CC = caudal cilium. Obj. 40 X.

Coleps-hirtus

Fig. 2 a-d: Coleps hirtus. L = 62 µm. A second freely swimming specimen. CC = caudal cilium, SP = posterior spines. Obj. 100 X.

Coleps-hirtus

Fig. 3 a-c: Coleps hirtus. L = 71 µm. A third freely swimming specimen. ASP = apical spines, CC = caudal cilium, MO = mouth opening. Obj. 100 X.

Coleps-hirtus

Fig. 4: Coleps hirtus. Two focal planes on the carapace of a squashed specimen. Obj. 100 X.

Coleps-hirtus

Fig. 5: Coleps hirtus. The pretzel-shaped “windows”(PW) in the carapace of a squashed specimen. Obj. 100 X.