Cephalodella catellina Müller, 1786
Most likely ID: n.a.
Synonym: n.a.
Sampling location: Bussenried
Phylogenetic tree: Cephalodella catellina
Diagnosis:
- body stout, dorsally curved, ventrally almost straight
- large head, distinct fold in neck
- oblique corona without lips
- cuticle flexibel
- length 90–160 µm (with toes)
- toes short, conical shaped, shifted to ventral side
- two frontal eyespots close together (visible in dorsal view)
- cerebral ganglion large and saccate
- retrocerebral organ absent
- trophi large, distal ends of manubria loop shaped
Up to now I have found Cephalodella catellina exclusively in the Bussenried and only a few specimens there. The specimen shown below was found in sample taken in November 2018. It was swimming near the surface of the sample.
The shape of Cephalodella catellina is very characteristic due to the short toes shifted to the ventral side. The posterior end is almost rectangular in shape. Due to the flexible cuticle, the shape is not constant and longitudinal and transverse folds are formed. Apically there are two eyespots that are close together. In lateral view, however, they appear as one eyespot.
More images and information on Cephalodella catellina: Michael Plewka-Freshwater life-Cephalodella catellina
Fig. 1 a-d: Cephalodella catellina. L = 110 µm (with toes). Different focal planes of a slightly squashed specimen. Note the ventrally shifted toes (TO). CG = cerebral ganglion, DA = dorsal antenna, ES = eyespot, Int = intestine, St = stomach, TR = trophi, Vit = vitellarium Obj. 100 X.