Ventral infraciliature of the oxytrichid,Gonostomum strenuum (ENGELMANN, 1862) STERKI, 1878. G. strenuum differs from G. affine by the greater number of frontoterminal (4-6 vs 2) and frontoventral cirri. In G. strenuum the last frontoventral cirrus is just posterior to the peristome (yellow arrowhead).Collected from a non-flooded Petri dish culture of soil from a park lawn in Boise, Idaho. January 2007.Stained by the protargol technique [Wilbert modification] (see Foissner, W. Europ. J. Protistol., 27:313-330;1991).Brightfield.