Ploima

Ribadelago de Franco, Castille and Leon, Spain

Galende, Castile and Len, Spain

Ribadelago de Franco, Castilla y Len, Espaa

Ribadelago de Franco, Castille and Leon, Spain

Ribadelago de Franco, Castille and Leon, Spain

Ribadelago de Franco, Castilla y Len, Espaa

San Martin De Castaneda, Castille and Leon, Spain

Galende, Castile and Len, Spain

Ribadelago de Franco, Castille and Leon, Spain

Los Cotos, Madrid, Spain

Trefacio, Castille and Leon, Spain

Pera, Faro, Portugal

The right posterior tip of the lorica wich is outcurved laterally. The posterior points of the lorica were short. Lorica lenght 88-100; lorica height 55-61; lorica width 45-50; toe lenght 21-24 micron ( Muller 1773 ).

Muelas del Pan, Castille and Leon, Spain

Keratella, a rotifer (metazoa). Rotifers typically have a stiffened body wall (lorica) in segments which can telescope, with a corona of feeding cilia at the anterior end and with toes posteriorly. This genus has no foot nor toe, as an adaptation to a pelagic life. Rotifers are common members of the microbial communities of many aquatic ecosystems. Although they are multicellular animals, they may be only be 100 microns long, and so overlap in size with ciliates. They can be confused with ciliates because they use cilia to capture their food. However, they can be distinguished because they have a lorica, may have podites, and a strong muscular pharynx.

Lepadella. Rotifer observed in sandy and muddy marine sediments in the vicinity of Broome, Western Australia in September 2003. This image was taken using phase contrast optics.   This work was supported by the Australian Biological Resources Study.

This is a bdelloid rotifer (metazoa), body with an exoskeleton usually in elements that will telescope, posterior end often with two podites (like gastrotrichs to which they are probably related). Very common in aquatic habitats especially those which are prone to dry out - like moss, soils and the contents of pitcher plants. They can resist drying because they can form cysts, but some species are known to be cryptobiotic - that is they can dry out completely, and the organisms can come back to life when wetted. Usually eat bacteria or suspended protists, using the cilia of the corona at the front end of the body to sweep particles into the front of the body where an armoured mastax or jawed pharynx helps to grind the food. Rotifers are common members of the microbial communities of many aquatic ecosystems. Although they are multiceullar animals, they may be only be 100 microns long, and so overlap in size with ciliates. They can be confused with ciliates because they use cilia to capture their food. However, they can be distinguished because they have an exoskeleton, usually two posterior toes, and a tough pharyngeal region just behind the head. Hendrik Seegers says this is probably a non-contracted Lecane because of the toes which appear to bear claws and the more or less regular lower half of the body, below the constriction. Phase contrast.

A somewhat withdrawn individual - rotifers can be like that. Differential interference contrast optics.

Rotifer, with two stiff blades to either side of the body and these can be extended. From Lake Donghu, China. Generic identification by Hendrik Seegers. Phase contrast micrograph.

Believed to be the egg of a rotifer. From Lake Donghu, China. Identified to genus by Hendrik Seegers. Phase contrast micrograph.

Monommata (mon-owe-mat-a), a rotifer (metazoa). Rotifers typically have an exoskeleton in segments which can telescope, with a corona of feeding cilia at the anterior end and with toes or podites posteriorly. This genus has very strongly developed toes, and muscle fibres can be seen within the toes. The toes can flick suddenly. Rotifers are common members of the microbial communities of many aquatic ecosystems. Although they are multiceullar animals, they may be only be 100 microns long, and so overlap in size with ciliates. They can be confused with ciliates because they use cilia to capture their food. However, they can be distinguished because they have an exoskeleton, usually two posterior toes, and a tough pharyngeal region just behind the head.

Monommata, a rotifer with two very long posterior spines. The spines are motile and can flex. Phase contrast micrograph.

This rotifer has two very long and retractible 'toes'. The ingestion region is to the left - some cilia of the wheel organ are visible. The body includes an ovary (lower) and gut (upper). Phase contrast microscopy.