Myiasis is infection with a fly larva, usually occurring in tropical and subtropical areas. There are several ways for flies to transmit their larvae to people.

• Some flies attach their eggs to mosquitoes and wait for mosquitoes to bite people. Their larvae then enter these bites.
• Other flies’ larvae burrow into skin. These fly larvae are known as screwworms. They can enter skin through people’s bare feet when they walk through soil containing fly eggs or attach themselves to people’s clothes and then burrow into their skin.
• Some flies deposit their larvae on or near a wound or sore, depositing eggs in sloughing-off dead tissue.
• See https://www.cdc.gov/parasites/myiasis/faqs.html

I am thinking of Conopidae, who lay their eggs on bumblebees etc, which then take these eggs into their nest.

In Syrphidae there are some examples. At least Rhingia campestris laying eggs on leaves overhanging cowdung (see Coe, 1942 Rhingia campestris life history ... Ent. mont Mag. 78: 121-130).

The species of the sub-family Pipizinae seem to lay their eggs away from the feeding substrate as these are gallforming Hemiptera and Syrphidae do not have a drilling ovipositor (see Rotheray 1997 Larval stages of ... Ent gaz. 48: 127-134 and van Steenis et al 2018 Trichopsomyia Iran Zoology in the Middle East 64: 345-359)

Many species (e.g. genera Merodon, Eumerus, Pipizella, Chrysotoxum) in which the larvae feed on bulbous plants or root aphids seems to lay eggs in the soil.

Black soldier flies (Hermetia illucens) typically lay eggs adjacant to or above decaying matter, but not directly into the decaying matter.

See the following paper for reference: Sheppard, D. C., Tomberlin, J. K., Joyce, J. A., Kiser, B. C., & Sumner, S. M. (2002). Rearing methods for the black soldier fly (Diptera: Stratiomyidae). Journal of Medical Entomology, 39(4), 695-698.

About Conopidae, I don't know of anyone who has published Conopidae larvae migrating from one host to the next. Just that they remain within one host, where the egg is laid upon.

The family that truly oviposits away from the feeding substrate is Acroceridae. Their larvae, when hatched from the egg, have special adaptations to move around and find a host. Spiders as far as I know.

Greetings,

Elias

In Bombyliidae, many species have larvae that are nest parasites of e.g. solitary bees. The deposit the eggs near the nest entrance and the first instar larvae enter the nest cells in search of the nest cells.

With regard to Conopidae: their larvae develop in the host. The female fly puts the egg inside the host (not on).