Guardian Nature School Team Contact Blog Project Noah Facebook Project Noah Twitter

A global community of nature enthusiasts
photographing and learning about wildlife

Join Project Noah!
nature school apple icon

Project Noah Nature School visit nature school

Braconid Wasp

Cotesia congregata


Less than l/8" long; hardly big enough to see. Predator wasp hatching from its cocoon on a Tomato Hornworm. Wasp eggs are laid inside the Hornworm's body where they hatch into larvae. The larva feed on the Hornworm's muscle tissues. Heart and other essential organs are not fed on until the larvae mature. The Hornworm remains alive but paralyzed and becomes a buffet of fresh food sustenance for the wasp larvae. In approximately a week the larvae mature, exit the Hornworm through a hole created in its skin and build a silken cocoon on the outside of the Hornworm. The larvae become adult wasps within the cocoon, hatch and fly off to find another Hornworm to infect.


Spotted in backyard garden on a tomato plant.


I have found the name "Braconid Wasp" in relation to these predator wasps but am not sure if this is right.

1 Species ID Suggestions

Fyn Kynd
Fyn Kynd 8 years ago
Braconid Wasp
Cotesia congregata Species Cotesia congregata - BugGuide.Net

Sign in to suggest organism ID


ElaineWebb 8 years ago

Thanks for the comments John La Salle, LaurenZarate, YukoChartraw, Darvesh, lori.tas and for the Favorites on this spotting. John La is, to us, horrible behavior; it seems so wrong for anything to feast on living flesh. I did not see the wasps leave the body of this Hornworm (and I'm not sorry for that). Hornworms are pests but they sure don't deserve this fate. This was the second Hornworm that met this fate in the garden this summer.

John La Salle
John La Salle 8 years ago

Yes, most find this type of behaviour horrible - but insect parasitism is extremely common.
We are not the only ones that might think this is horrible - I will repost one of my favourite quotes from Charles Darwin.
"I cannot persuade myself that a beneficent and omnipotent God would have designedly created parasitic wasps with the express intention of their feeding within the living bodies of caterpillars"

LaurenZarate 8 years ago

Wow! Amazing series and wonderful photographs....and horrible too.

YukoChartraw 8 years ago

Incredible! Amazing find!

Darvesh 8 years ago

Unbelievable Horrendous !!

lori.tas 8 years ago

Fantastic series.

John La Salle
John La Salle 8 years ago

Elaine - yes you are right these are Braconidae in the subfamily Microgastrinae.
Nice series of pictures. It is really pretty horrible to watch the larvae actually emerge from the still living caterpillar to start spinning their cocoons.

Spotted by

Connecticut, USA

Spotted on Aug 21, 2013
Submitted on Aug 21, 2013

Noah Guardians
Noah Sponsors
join Project Noah Team

Join the Project Noah Team