Life table studies on endoparasitoids are complicated by the fact that there will be unobservable life stages, i.e., larval development of the parasitoid. You may want to supplement standard life table data collection where you are monitoring survival, molting, and reproductive parameters on a daily basis with destructive host dissections to determine larval development and survival. Also, it can be difficult to determine fecundity of adult parasitoids in the lab unless you know something about the host finding behavior, egg maturation strategy, and host density response. Even then it can be unrealistic as parasitoids often forage widely and funny things can happen when they are confined. There aren't a lot of life tables for parasitoids in the literature, possibly because of these and other complications such as concurrently maintaining the host in culture.

Thank you NG Wiman and SRN Campero for your valuable suggestion.

Hi,

I have been studying the endoparasitoid live stages (A. ervi in Aphids). The only way is to dissect the individuals every 24 h and determine the developmental stage of the endoparasitoid. It is a very hard work since you won,t have a 100 % parasitization rate in the aphid, so many of the aphid you will dissected for nothing, and also this task is very time consuming.

Dear Colleagues,

Very interesting topic. I agree that it is very difficult to study the larval stages of parasitoids. In our lab we did a study of the biology of Brethesiella sp. (Hymenoptera: Encyrtidae). I say biology, because as I understand, to do Life Tables you have to start with a cohort and follow its development until adult, then longevity, etc. BUT, like Nik has written above, the only way of following the development of the parasitoid larva is through destructive host dissections, so there goes the Life Table. If there was an insect X-ray machine.. but I do not know of such device. 

What we did was to start with a parasitoid-free population of monophlebids (the host of the parasitoid) and add virgin female wasps to one group of monophlebids, and add couples (male and female) of wasps to another group of monophlebids. That is how we determined the type of reproduction. Unfertilized females do produce viable eggs, but of only one particular sex (cannot say more until our work is published). Once the student carefully observes the parasitoids, he or she will record the time of oviposition of the parasitoid on the host. You have to start with a high number of parasitized hosts and do daily dissections, This way we were able to determine the duration of all three larval instars and the pupae. It is a lot of work but results are satisfying. 

If you have no time, nor patience nor a good student, then the option given by Segundo is the way to go. Most studies on parasitoids appear to have been done the way Segundo has explained. Our study lasted a year, with lots of trial and error. Good luck!

It would be great if Takumaso Kondo could share his publication with us once it is published. It seems to be an interesting work. I would definitely be like to have a copy please, as I also hope to start a study on an endoparasite of coconut black headed caterpillar.

Montealegre, X.; Sotelo, P.; Kondo, T. 2016. Development and Reproduction of Brethesiella cf. abnormicornis (Girault) (Hymenoptera: Encyrtidae), a Parasitoid of the Colombian Fluted Scale, Crypticerya multicicatrices Kondo & Unruh (Hemiptera: Monophlebidae). Environmental entomology. 8 pp. doi: 10.1093/ee/nvw004.

The above was recently published (see attached online version of the paper). Studying life table parameters of endoparasitoids is not and easy task which involves many dissections. In some species of Coccidae, the development of the endoparasitoid can be observed through the semitransparent cuticle, but that was not the case in our study.