Metabetaeus minutus is a species of alpheid shrimp native to the Indo-West Pacific.

[3][2] The average size can range depending on the population, with the smallest collected from Fakaofo being 12 mm long and largest known specimen being collected from Jaluit Atoll at 17 mm long.

[2] M. minutus can be found inhabiting landlocked anchialine pools, containing brackish water.

[2] Populations can also be found living in anchialine caves and brackish pools in mangrove swamps.

[2] M. minutus have been recorded to coinhabit their pools with crab species such as Ptychognathus easteranus.