Lepadella ovalis (O. F. Müller, 1786)
Most likely ID: n.a.
Synonym: n. a.
Sampling location: Ulmisried, Purren pond, Mainau pond, Simmelried
Phylogenetic tree: Lepadella ovalis
Diagnosis:
- lorica subcircular to ovate, dorso-ventrally compressed
- length of lorica 93–153 µm, width 94–100 µm
- dorsal side slightly convex, ventral side flat
- dorsal sinus U-shaped, ventral sinus subrhomboid
- lorica transparent with a distinct hyaline fringe on the inside
- small opening for the head
- foot groove is parallel-sided, edges of the groove project below the surface of the ventral plate
- three foot segments, toes pointed
Lepadella ovalis is very common in my sites throughout the year. This rotifer can be found mostly in floating plant masses. Lepadella ovalis can be recognized quite well by the hyaline fringe on the inner side of the lorica (s. figs. 1 and 3). The specimens shown here were found in Simmelried in September 1995 (fig. 1) and in January 1999 (fig. 2) and March 2023 (fig. 3).
More images and information on Lepadella ovalis: Michael Plewka-Freshwater life-Lepadella ovalis
Fig. 1: Lepadella ovalis. L = 136 µm (of the lorica). Ventral view of a slightly squashed specimen with a fully extended foot. HF = hyaline fringe. Obj. 40 X.
Fig. 2: Lepadella ovalis. L = 145 µm (of the lorica). Ventral view of a second slightly squashed specimen with a fully extended foot. Obj. 40 X.
Fig. 3: Lepadella ovalis. L = 154 µm (of the lorica). Ventral view of a slightly squashed specimen with a fully extended foot. HF = hyaline fringe. Obj. 60 X.
Fig. 4: Lepadella ovalis. L = 125 µm (of the lorica). Ventral view of a slightly squashed specimen with a fully extended foot. Note the granulated fringe of the ventral sinus (arrow). Obj. 60 X.
Fig. 5 a-b: Lepadella ovalis. L = 125 µm (of the lorica). Two focal planes of a dorsal view. Note the granulated fringe of the dorsal sinus (arrow, 5b). Obj. 60 X.