Comamonas sp. is restricted to the gut epithelium of Spirocerca lupi L3 larva. Images of fluorescence in-situ hybridization analysis of S. lupi L3 larva stained with Comamonas-specific probe (green), detected using confocal microscopy. (a) No-probe control; (b) Intact L3; (c, d) Ruptured L3; (e) Enlargement of (d), showing specific signal in the larval gut; (f) One optical section showing a specific signal only in the gut epithelium region. The arrow points to a specific focal point. All images but (f) are combined optical Z sections, overlaid on a bright-field image.