Homalozoon vermiculare

Ribadelago de Franco, Castille and Leon, Spain

Portrait of large haptorid ciliate Homalozoon vermiculare (STOKES,1887)STOKES,1890. Laterally flattened. Bluntly rounded anteriorly and tapered posteriorly. Contractile. Slit-like oral aperture with prominent oral bulge extrusomes. Multiple small contractile vacuoles along lateral margin. Macronucleus moniliform. Brightfield. From standing freshwater with abundant decomposing leaves near Boise, Idaho.

Detail of anterior of Homalozoon vermiculare (STOKES,1887) STOKES,1890 showing dense collection of oral bulge extrusomes. The characteristic dense anterior aggregate of pharyngeal granules is well seen. The function of these is unclear. Brightfield. From freshwater pond near Boise, Idaho.

Homalozoon vermiculare (STOKES,1887) STOKES,1890 seen here preying on a peritrich ciliate. The characteristic dense aggregate of granules can be seen. This is displaced by the ingested prey and then disperses as the food vacuole proceeds distally. From freshwater pond near Boise, Idaho. Brightfield

This cell has been killed and then stained with Feulgen stain which shows up the nuclei. As with all ciliates, there are two kinds of nuclei, a large macronucleus which takes the form of a string of beads, and smaller micronuclei which in this species are numerous small structures located near the macronucleus.

Phase contrast micrograph of a living cell. The line of contractile vacuoles, lines of the kineties and the band of extrusomes just under the mouth are visible.

Infraciliature (right side) of Homalozoon vermiculare (STOKES,1887) STOKES,1890.Collected from a eutrophic freshwater pond in Boise,Idaho June 2008.Stained by the Protargol A technique (see Foissner, W. Europ. J. Protistol., 27:313-330;1991).Brightfield.

Infraciliature (ventral side) of Homalozoon vermiculare (STOKES,1887) STOKES,1890. the posterior portion of the moniliform macronucleus and one of the numerous micronuclei are seen here.Collected from a eutrophic freshwater pond in Boise,Idaho June 2008.Stained by the Protargol A technique (see Foissner, W. Europ. J. Protistol., 27:313-330;1991).Brightfield.

Infraciliature (right side) of Homalozoon vermiculare (STOKES,1887) STOKES,1890. CK=circumoral kinety.OA=oral aperture.RSK=right somatic kineties.Collected from a eutrophic freshwater pond in Boise,Idaho June 2008.Stained by the Protargol A technique (see Foissner, W. Europ. J. Protistol., 27:313-330;1991).Brightfield.

Infraciliature (ventral side) of Homalozoon vermiculare (STOKES,1887) STOKES,1890. CK=circumoral kinety.DB=dorsal brush.LSK=left somatic kineties.Collected from a eutrophic freshwater pond in Boise,Idaho June 2008.Stained by the Protargol A technique (see Foissner, W. Europ. J. Protistol., 27:313-330;1991).Brightfield.