Hymenoepimecis argyraphaga is a Costa Rica

Costa Rica

Costa Rica , officially the Republic of Costa Rica is a multilingual, multiethnic and multicultural country in Central America, bordered by Nicaragua to the north, Panama to the southeast, the Pacific Ocean to the west and the Caribbean Sea to the east....

n 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...

 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...

 whose host is the spider

Spider

Spiders are air-breathing arthropods that have eight legs, and chelicerae with fangs that inject venom. They are the largest order of arachnids and rank seventh in total species diversity among all other groups of organisms...

 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 adult female wasp temporarily paralyzes the spider and lays an egg on its abdomen. The egg hatches into a 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...

 which sucks the spider's blood through small holes, while the spider goes on about its normal web building and insect catching behavior for the next one to two weeks. When the larva is ready 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, it injects a chemical into the spider, causing it to build a web whose design is completely different from any it has ever made, and then to sit motionless in the middle of this web. Even if the larva is removed prior to the web-building process, the spider still engages in aberrant web-spinning. The wasp larva then molts, kills the spider with a poison and sucks its body dry before discarding it and building a cocoon that hangs from the middle of the web the spider has just built. The larva pupates inside the cocoon, then emerges to mate and begin the cycle over again.

Behavior alteration

Normal orb weaving consists of several steps:

1. Build non-sticky frame lines attached to supporting objects and a few initial radial lines. This process sometimes involves establishing connections with surrounding objects by floating a line in the wind and hoping it catches somewhere.
2. Add more non-sticky radial lines attached to these frame lines, in some cases adding at the same time less peripheral, "secondary" frame lines.
3. Add several tight loops of non-sticky silk at the hub of the web.
4. Lay a loose "temporary" spiral of non-sticky silk, starting near the hub and ending near the edge of the web with about five times the spacing of the final sticky silk.
5. Draw the tight spiral of sticky silk starting at the edge of the web and working inward, and removing during the same process the loose spiral.
6. Remove lines at the center of the hub, leaving a hole or (in some species) replacing them with other lines

The modified web that the larva causes the spider to build consists of several heavily reinforced radial lines that are attached directly to the substrate; sometimes one or more frame lines or vestiges of a "temporary" spiral are also included. The reinforced lines are built using a subset of the same sequence of movements that the spider performs during the construction of frame lines in the normal orb, repeated many times over. Thus the larva appears to be able to induce very specific behavioral responses in the spider.

The lifecycle of the wasp was filmed for the BBC series Life in the Undergrowth (programme 4 in the series, Intimate Relations).

See also

• Glyptapanteles
  Glyptapanteles
  Glyptapanteles is a genus of endoparasitoid wasp found in Central and North America. The larvae of the members of Glyptapanteles sp. are distinguished by their ability to manipulate their hosts into serving as bodyguards.-Reproduction:...
  
  , a genus of parasitoid wasp with a similar larval capacity 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.