Mymarommatidae
Encyclopedia
Mymarommatidae is a very small family of microscopic hymenoptera
n insect
s. Only 10 living species in 1 genus have currently been described (others are known only as 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 ovipositor
, it is assumed by entomologists that they are idiobiont parasitoid
s 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
.
s", the sole surviving lineage of an otherwise extinct superfamily Serphitoidea. It remains to be seen whether this change in classification will be accepted, but it has some significant support.
Hymenoptera
Hymenoptera is one of the largest orders of insects, comprising the sawflies, wasps, bees and ants. There are over 130,000 recognized species, with many more remaining to be described. The name refers to the heavy wings of the insects, and is derived from the Ancient Greek ὑμήν : membrane and...
n insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
s. Only 10 living species in 1 genus have currently been described (others are known only as 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
Biology
Biology is a natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy. Biology is a vast subject containing many subdivisions, topics, and disciplines...
of these insects but because of their size, and simple ovipositor
Ovipositor
The ovipositor is an organ used by some animals for oviposition, i.e., the laying of eggs. It consists of a maximum of three pairs of appendages formed to transmit the egg, to prepare a place for it, and to place it properly...
, it is assumed by entomologists that they are idiobiont parasitoid
Parasitoid
A parasitoid is an organism that spends a significant portion of its life history attached to or within a single host organism in a relationship that is in essence parasitic; unlike a true parasite, however, it ultimately sterilises or kills, and sometimes consumes, the host...
s on the eggs
Egg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...
of various insects. They were originally treated as an aberrant subfamily of the chalcidoid family Mymaridae but, because of morphological
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
differences, are now usually considered in their own superfamily, Mymarommatoidea, and their similarity to Mymaridae is thought to be a result of convergent evolution
Convergent evolution
Convergent evolution describes the acquisition of the same biological trait in unrelated lineages.The wing is a classic example of convergent evolution in action. Although their last common ancestor did not have wings, both birds and bats do, and are capable of powered flight. The wings are...
.
Classification
As taxonomists have examined this group more closely, they have become less and less certain about which other group of wasps represents the nearest living relatives of the Mymarommatidae. In recent years, some have claimed that the nearest relatives are the extinct family Serphitidae, and therefore claim that the Mymarommatidae are essentially "living fossilLiving fossil
Living fossil is an informal term for any living species which appears similar to a species otherwise only known from fossils and which has no close living relatives, or a group of organisms which have long fossil records...
s", the sole surviving lineage of an otherwise extinct superfamily Serphitoidea. It remains to be seen whether this change in classification will be accepted, but it has some significant support.