M. savartii forms encrusting colonies that may be one or more layers thick. Zooid shape varies from elongate to rectangular or quadrangular. Individuals measure an average of 0.27 X 0.55 mm. A variable denticulated (toothed) shelf is formed under the proximal half of the frontal surface. Proximal teeth are variable in number or absent. Zooid walls are heavily calcified and have fine tubercles. No avicularia are present.