A confocal laser scanning micrograph of a paraffin section from a maize leaf infected with corn stunt spiroplasma (CSS, Spiroplasma kunkelii, Class Mollicutes), that has been labeled with primary CSS antibodies then with secondary antibodies (Alexa Fluor-488, green), and stained with the nuclear stain propidium iodide (red), showing CSS aggregates (green areas) in the phloem. CSS is a wall-less procaryote that causes corn stunt disease and is biologically transmitted by some leafhopper species, e.g. Dalbulus maidis and D. gelbus (Hemiptera, Cicadellidae). Spiroplasma cells are limited by a unit membrane with no cell wall. They can be quasi-spherical, pleiomorphic or maintain a filamentous/spiral form. CSS multiplies in both plant and insect hosts and is transmitted with salivary secretions during feeding of the vector on new host plants.