July 2018 The pith inside last year's long-dead flowering stalks of prairie Indian-plantain,
Arnoglossum plantagineum, is riddled with insect tunnels and spent agromyzid fly puparia...the prolific flies did quite a nice job of beginning the decomposition of these stalks.
Puparium from inside one of the stalks:
Larva from inside one of the stalks:
Something similar, from a woodland
Arnoglossum (different species) in 2017: