Protomonaxonid sponges standing around (as sponges do) on the enthusiastically bioturbated sediment of the Fezouata Shale, 478 million years ago in the Antarctic Circle.

These early demosponges have been given the rather cumbersome designation of 'Hamptonia' christi Form B, pending a formal description. Standing a few centimeters tall, they (and several other sponges found in Fezouata) formed dense but single-species assemblages interpreted as rapid and repeated colonization events in a hostile environment (Botting 2016).

I could not resist giving them the same coloration as their fossils, which are beautifully rendered in hues of iron oxides. Surely reds and oranges aren't unusual colors for sea sponges?

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