Limnias melicerta – Real Micro Life

Limnias melicerta Weisse, 1848

Most likely ID: n.a.

Synonym: n.a.

Sampling location: Simmelried

Phylogenetic tree: Limnias melicerta

Diagnosis:

sessile rotifer in a transparent tube ornamented with rings
tube commonly orange or brownish, up to 960 µm
length up to 1540 µm
corona with 2 lobes with wide dorsal gap
dorsal antennae short, ventral antennae long
about 7 horns in the neck region (number variable)
amictic eggs are deposited in tube
eyespots absent

So far I have only been able to find Limnias melicerta in the Simmelried, where the species is quite rare. I either find the specimens on the leaves of Utricularia or (in rare cases) specimens settle on the floating coverslip. According to Voigt (1957), Limnias melicerta particularly likes to settle on the underside of water lily leaves.

Limnias melicerta cannot be confused with any other species due to the shape of its self constructed tube. This consists of secretion rings, which are periodically deposited by the rotifer and subsequently harden (s. fig. 3 b). The tube is transparent, flexible and usually orange-brown in color.

The corona consists of two, almost circular lobes with an incision in the middle. On the dorsal side, below the corona, there are usually 7 so-called horns. These are best recognized on contracted specimens (s. fig. 4). They are characteristic for Limnias melicerta.

More images and information on Limnias melicerta: Michael Plewka-Freshwater life-Limnias melicerta

Fig. 1 a-b: Limnias melicerta. L = 800 µm. Two focal planes of a specimen in a orange-brownish tube. Obj. 10 X.

Fig. 2 a-b: Limnias melicerta. L = 780 µm. Two focal planes of a second specimen. Obj. 20 X.

Fig. 3 a-b: Limnias melicerta. L = 800 µm. Two focal planes of slightly squashed specimen. Note the amictic egg (AE) deposited in the tube. SR = secretory rings. Obj. 10 X.