The Mymarommatidae are a very small family of microscopic hymenopteran insects. Only about half of the known species are living taxa (the others are fossils), but they are known from all parts of the world. Undoubtedly, many more await discovery, as they are easily overlooked and difficult to study due to their extremely small size (most have an overall length of around 0.3 mm).
Virtually nothing is known about the biology of these insects, but because of their size, and simple ovipositors, entomologists assume they are idiobiont parasitoids on the eggs of various insects. They were originally treated as an aberrant subfamily of the chalcidoid family Mymaridae but because of morphological differences, are now usually considered in their own superfamily, Mymarommatoidea, and their similarity to Mymaridae is thought to be a result of convergent evolution.