Glyptapanteles
Encyclopedia
Glyptapanteles is a genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of endoparasitoid
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...

 wasp
Wasp
The term wasp is typically defined as any insect of the order Hymenoptera and suborder Apocrita that is neither a bee nor an ant. Almost every pest insect species has at least one wasp species that preys upon it or parasitizes it, making wasps critically important in natural control of their...

 found in Central and North America. 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 members of Glyptapanteles sp. are distinguished by their ability to manipulate their hosts into serving as bodyguard
Bodyguard
A bodyguard is a type of security operative or government agent who protects a person—usually a famous, wealthy, or politically important figure—from assault, kidnapping, assassination, stalking, loss of confidential information, terrorist attack or other threats.Most important public figures such...

s.

Reproduction

Female Glyptapanteles oviposit
Oviposition
Oviposition is the process of laying eggs by oviparous animals.Some arthropods, for example, lay their eggs with an organ called the ovipositor.Fish , amphibians, reptiles, birds and monetremata also lay eggs....

 into caterpillar
Caterpillar
Caterpillars are the larval form of members of the order Lepidoptera . They are mostly herbivorous in food habit, although some species are insectivorous. Caterpillars are voracious feeders and many of them are considered to be pests in agriculture...

 hosts. Species parasitized by Glyptapanteles include Lymantria dispar
Gypsy moth
The gypsy moth, Lymantria dispar, is a moth in the family Lymantriidae of Eurasian origin. Originally ranging from Europe to Asia, it was introduced to North America in the late 1860s and has been expanding its range ever since...

, as well as Chrysodeixis chalcites and Thyrinteina leucocerae (both pictured). The caterpillar continues to grow and feed normally until the 4th or 5th instar
Instar
An instar is a developmental stage of arthropods, such as insects, between each molt , until sexual maturity is reached. Arthropods must shed the exoskeleton in order to grow or assume a new form. Differences between instars can often be seen in altered body proportions, colors, patterns, or...

, whereupon up to 80 fully grown larvae emerge from its body to pupa
Pupa
A pupa is the life stage of some insects undergoing transformation. The pupal stage is found only in holometabolous insects, those that undergo a complete metamorphosis, going through four life stages; embryo, larva, pupa and imago...

te.

Behavior alteration

After the larvae of Glyptapanteles sp. emerge, the caterpillar takes up position near the cocoons of the pupae, arches its back, and ceases to move or feed. It will occasionally spin silk over the pupae. However, when disturbed, it begins to thrash violently. No longer inclined to eat, the affected caterpillar eventually dies. It has been demonstrated in experimental research (Grosman, et al.) that this behavior is to strike at and repel possible predators of the pupae, such as the shield bug
Shield bug
Pentatomoidea is a superfamily of insects in the Heteroptera suborder of the Hemiptera order and, as such, share a common arrangement of sucking mouthparts...

 Supputius cincticeps, thus improving their survival odds. Only about one in twenty non-parasitized caterpillars responded in this fashion. In 60% of cases, the parasitized caterpillars successfully warded off these potential predators. Mortality rates for pupae not guarded by parasitized caterpillars were significantly higher. That it is of no demonstrated benefit to the caterpillar indicates that this is an adaptation on the part of Glyptapanteles.

Mechanism

In the course of Grosman's research, it was discovered that not all larval Glyptapanteles emerge from their caterpillar host. One or two remain behind and active. Grosman has theorized that these larvae manipulate the host, foregoing their own chance at pupating in order to protect the brood.

Biocontrol

G. flavicoxis, G. porthetriae and G. militaris have been evaluated by the USDA as possible bio-control
Biological pest control
Biological control of pests in agriculture is a method of controlling pests that relies on predation, parasitism, herbivory, or other natural mechanisms...

 agents for containing the invasive gypsy moth (Lymantria dispar) population in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

. Research has indicated that Pseudaletia unipuncta hosts fed fresh perennial ryegrass (Lolium perenne
Lolium perenne
Lolium perenne, common name Perennial Ryegrass, is a grass from the family Poaceae. It is native to Europe, Asia and northern Africa, but is widely cultivated and naturalised around the world.-Description:...

) leaves are optimal for the mass-breeding of G. militaris.

See also

  • Hymenoepimecis argyraphaga
    Hymenoepimecis argyraphaga
    Hymenoepimecis argyraphaga is a Costa Rican parasitoid wasp whose host is the spider Plesiometa argyra. The wasp is unique in modifying the spider's web building behavior to make a web made of very strong lines designed to support the wasp's cocoon without breaking in the rain.-Reproduction:The...

    , a species of parasitoid wasp with similar larval ability to manipulate hosts to its own ends.
  • Ampulex compressa
    Emerald cockroach wasp
    The emerald cockroach wasp or jewel wasp is a solitary wasp of the family Ampulicidae. It is known for its unusual reproductive behavior, which involves stinging a cockroach and using it as a host for its larvae...

    , or the "Emerald cockroach wasp", a wasp capable of debilitating cockroaches into serving as docile hosts for its eggs.

External links

  • Video - A parasitized caterpillar, bent over the parasitoid pupae that have egressed from it, defends itself and the parasitoid pupae against a predator with violent head-swings, resulting in the predator being knocked off the twig.
  • Video - A non-parasitized caterpillar hardly responds to a predator.
  • Photographs of Glyptapanteles phytometrae in cocoon, larval, and pupal phases.
  • Photographs of adult specimens at BOLD Systems Taxonomy Browser.
  • Article with video at NewScientist.
  • Taxonomic information at UniProt Consortium and NCBI.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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