Microcotyle toba is a species of monogenean, parasitic on the gills of a marine fish.

The haptor is narrow, not well delineated from body proper, and bears 23 pairs of clamps.

The digestive organs include an anterior, terminal mouth, a small oval muscular pharynx, a very short oesophagus and a posterior intestine with two lateral branches provided with many ramifications which enters the vitellaria.

The reproductive organs include an anterior genital atrium armed with numerous conical pointed slightly recurved spines, a dorsal vagina, a single S-shaped ovary, 25-30 of follicular testes which are postovarian and situated in the intercecal field.

[3] The type-host of Microcotyle toba is the mottled spinefoot Siganus fuscescens (Siganidae).