At least I think they're seed pods. I noticed these strange looking things growing all over the surface of my mulch.
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They look like tiny black cupcake papers containing small black disk shaped seeds. The cupcake things are firmly attached to pieces of mulch. Nearby plants include a Euphorbia Milli, Pregnant Onion, Day Lilly, and Bromeliad. I've tried some online research on seed pods for each of these plants but haven't come up with any definitive answers. If I had to guess I'd say they came from Euphorbia. I've included photos. Can anyone ID them?