A slime mould that looks remarkably like blackberries.
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You are probably right, the other possibilities being a Badhamia (utricularia or cineria).
Linbladia (there is only one species) starts of as white plasmodium and passed through brown to black/grey. Badhamia starts off as bright yellow plasmodium.
After much hunting on iNaturalist and getting some better shots of the stipe and following the progression (towards a beautiful blue sporangium) we are tending towards B. utricularia. Thanks for the heads up.
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