HYMENOPTERA, Mymerommatidae (= Callimomidae) (Mymarommantoidea)
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Mymerommatidae (= Callimomidae)
This is a very small family of microscopic Hymenoptera. Only 11 living species in 1 genus have been described, but others are known only as fossils. They have a worldwide distribution. More species await discovery, as they are easily overlooked and difficult to study due to their extremely small size (most have an overall length of around 0.32 mm).
Little is known about the biology of these wasps but because of their size, and simple ovipositor, it is believed that they are idiobiont parasitoids on the eggs of other insects. They had been treated as an atypical subfamily of the family Mymaridae but, because of morphological differences, are now usually placed in their own superfamily, Mymarommatoidea, and their similarity to Mymaridae is probably a result of convergent evolution.
There is no agreement about which other group of wasps represents the nearest living relatives of the Mymarommatidae. Some specialists have claimed that the nearest relatives are the extinct family Serphitidae, and therefore claim that the Mymarommatidae are essentially "living fossils", the sole surviving lineage of an extinct superfamily Serphitoidea.