Ventral infraciliature

Description :

Ventral view of the infraciliature of Metopus palaeformis (Kahl,1927) contracted by fixation and compressed to display details.Synonyms probably include Tesnospira alba (Jankowski,1964),M. hyalinus (Kahl,19270 and M. tenuis (Kahl,1927) among others.Morphology is highly variable probably explaining the large number of synonyms. The cell is flask-shaped (as in this example)to elongate .The anterior end is twisted to the left resulting in a rounded lip that overhangs the peristome.The spiral peristome is bordered on the left by an adoral zone of membranelles (arrow) and on the right by five closely spaced kineties,the "perizonal stripe" (large arrowhead).Just to the right of the posterior termination of the AZM is a short, inconspicuous undulating membrane(small arrowhead).The cytoplasm contains endosymbiotic methanogenic bacilli (not seen here).Collected from the bottom sediments of an organically enriched rain pool with abundant decaying grass contaminated by Canada goose (Branta canadensis) droppings.Boise, Idaho. January 2006.Stained by the silver carbonate technique (see Foissner, W. Europ. J. Protistol., 27:313-330;1991).Brightfield.