Encyrtidae is a large family of parasitic wasp

Parasitic wasp

The term parasitoid wasp refers to a large evolutionary grade of hymenopteran superfamilies, mainly in the Apocrita. They are primarily parasitoids of other animals, mostly other arthropods...

s, with some 3710 described species in some 455 genera (see List of encyrtid genera). The larva

Larva

A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...

e of the majority are primary 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 Hemiptera

Hemiptera

Hemiptera is an order of insects most often known as the true bugs , comprising around 50,000–80,000 species of cicadas, aphids, planthoppers, leafhoppers, shield bugs, and others...

, though other hosts are attacked, and details of the life history can be variable (e.g., some attack eggs, some attack larvae, others are hyperparasite

Hyperparasite

A hyperparasite is a parasite whose host is a parasite. This form of parasitism is especially common among entomophagous parasites....

s and there are even Encyrtidae that develops as parasitoids of tick

Tick

Ticks are small arachnids in the order Ixodida, along with mites, constitute the subclass Acarina. Ticks are ectoparasites , living by hematophagy on the blood of mammals, birds, and sometimes reptiles and amphibians...

s). They are found throughout the world in virtually all habitats, and are extremely important as biological control agents.

Some species exhibit a remarkable developmental phenomenon called "polyembryony

Polyembryony

Polyembryony is the phenomenon of two or more embryos developing from a single fertilized egg . Polyembryony occurs regularly in many plants and animals. The nine banded armadillo, for instance, usually gives birth to four identical young...

", in which a single egg multiplies clonally in the host and produces large numbers of identical adult wasps. Even more remarkably, some of the larvae are larger than the others and act in a similar way to the "soldiers" of eusocial insects, attacking any other wasp larvae already in the body of the host, and dying without reproducing ("altruism

Altruism

Altruism is a concern for the welfare of others. It is a traditional virtue in many cultures, and a core aspect of various religious traditions, though the concept of 'others' toward whom concern should be directed can vary among cultures and religions. Altruism is the opposite of...

").

Wasps in this family are relatively easy to separate from other Chalcidoidea by features of the wing venation, the migration of the cerci

Cercus

Cerci are paired appendages on the rear-most segments of many arthropods, including insects and arachnids but not crustaceans. Cerci often serve as sensory organs, but they may also be used as weapons or copulation aids, or they may simply be vestigial structures.Typical cerci may appear to be...

 forwards on the metasoma

Metasoma

The metasoma is the posterior part of the body, or tagma, of arthropods whose body is composed of three parts, the other two being the prosoma and the mesosoma. In insects, it contains most of the digestive tract, respiratory system, and circulatory system, and the apical segments are typically...

 (and accompanying distortion of the tergites), and a greatly enlarged mesopleuron

Pleuron (insect)

The pleuron is a lateral sclerite of thoracic segment of an insect between the tergum and the sternum. The terms pro-, meso- and metapleuron are used respectively for the pleura of the first, second and third thoracic segments....

 with anteriorly-positioned mesocoxae.

External links

• Universal Chalcidoidea Database
• Image Database TOBIKOBACHI Based on the Encyrtid Wasp Collection of Dr. T. Tachikawa
• Ageniaspis citricola on the UF
  University of Florida
  The University of Florida is an American public land-grant, sea-grant, and space-grant research university located on a campus in Gainesville, Florida. The university traces its historical origins to 1853, and has operated continuously on its present Gainesville campus since September 1906...
  
   / IFAS
  Institute of Food and Agricultural Sciences
  The University of Florida’s Institute of Food and Agricultural Sciences is a federal-state-county partnership dedicated to developing knowledge in agriculture, human and natural resources, and the life sciences, and enhancing and sustaining the quality of human life by making that information...
  
    Featured Creatures Web site
• Diaphorencyrtus aligarhensis on the UF
  University of Florida
  The University of Florida is an American public land-grant, sea-grant, and space-grant research university located on a campus in Gainesville, Florida. The university traces its historical origins to 1853, and has operated continuously on its present Gainesville campus since September 1906...
  
   / IFAS
  Institute of Food and Agricultural Sciences
  The University of Florida’s Institute of Food and Agricultural Sciences is a federal-state-county partnership dedicated to developing knowledge in agriculture, human and natural resources, and the life sciences, and enhancing and sustaining the quality of human life by making that information...
  
  Featured Creatures Web site