The tubules of so called capillitium have formed inside the sporangia of Panama myxomycete Perichaena longipes. Myxomycetes are giant amoebae, capable to form fungi-like fruiting.
<a href="//commons.wikimedia.org/wiki/User:%D0%94%D0%BC%D0%B8%D1%82%D1%80%D0%BE_%D0%9B%D0%B5%D0%BE%D0%BD%D1%82%D1%8C%D1%94%D0%B2" title="User:Дмитро Леонтьєв">Дмитро Леонтьєв</a>
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