Answer:
rod-shaped
Step-by-step explanation:
Bacteria in the genus Thiobacilli are classified within the order Pseudomonadales. They are small, rod-shaped cells (0.5 by 1–3.0 µm) which may be motile or nonmotile. Motility is due to a single polar flagellum. Bergey's Manual (1957) lists nine species, most of which are aerobic.