Genus Microdon

the nearcticWalton and over a dozen spp. worldwide are not placed to subgenera

Identification

The larvae are round and dome-like, often with a reticulate patterning and a conspicuous single tubercle posteriorly (above the rim of the "dome") formed by the fused posterior spiracles.



Puparia look just like larvae but have two well-separated, nipple-like anterior horns (spiracles) which appear ~2 days after pupation.



Adults are medium-sized bee-mimics with distinctive long antennae.



Mating pair





Identification to species may be difficult. Having matched puparium + adult can be very helpful; knowing the host also helps. Puparia are typically found near the periphery of the nest and are relatively easy to rear. If you find an adult flying or perched, it's a good idea to scan the surrounding area for potential host nest, such as Formica mound, or a Camponotus nest in wood or soil.