The leaves are round but may sometimes have very broad-based shallow teeth. The leaf cells have no trigones or small and concave ones. Oil bodies are elongated and dark brown.

In very wet conditions, M. surculosum may sometimes be found growing on the ground and be mistaken for Tylimanthus pseudosaccatus. The latter species however the marsupium developing at the shoot tip and the leaves have small teeth all around the margins while M. surculosum has the marsupium developing at the base of the stem and the leaves may have an occasional large tooth.