Lepadella triba (Myers, 1934)
Most likely ID: n.a.
Synonym: n.a.
Sampling location: Simmelried
Phylogenetic tree: Lepadella triba
Diagnosis:
- lorica elongated, slenderly oval
- length (of lorica) 60–82 µm
- toes very slender and long (22–32 µm) with pointed tips
- ventral plate flat, bordered by two lateral furrows
- dorsal plate evenly arched
- foot groove parallel sided
- terminal foot segment longer than rest
- two eyespots with lenses
- parasitic lifestyle on sponges
So far I have found only one specimen of Lepadella triba in a sample from the Simmelried. That I do not find the species more frequently may be due to its parasitic lifestyle. Lepadella triba gnaws the surface of freshwater sponges (Berzins, 1950). I have not been able to observe this interesting process myself, however, however, according to Berzin the specimens are supposed to bite down on the feeding site and cannot be detached without further ado. This may explain why they are rarely found freely swimming.
Lepadella triba is very easily recognized by two lateral furrows that border the flat ventral plate (s. fig. 1 b). The lorica itself is elongated oval. In addition, Lepadella triba has very long, slender toes that end with sharp points (s. fig. 2).
More images and information on Lepadella triba: Michael Plewka-Freshwater life-Lepadella triba
Fig. 1 a-d: Lepadella triba. L = 76 µm (of lorica). Different focal planes from ventral of a freely swimming specimen. Note the ventral plate (VP) bordered by two lateral furrows (LF). CO = corona. Obj. 60 X.
Fig. 2: Lepadella triba. L = 76 µm (of lorica). The slightly squashed specimen shown in fig. 1 a-d from ventral. Note the small lense (LE) of the eyespot (ES). FS = foot segments, TO = toes, VP = ventral plate. Obj. 100 X.
Fig. 3: Lepadella triba. The trophi in a strongly squashed specimen. Obj. 100 X.