Annulus relaxation and spore ejection, recorded with 20.000 fps. The beginning of the slow return (the second relaxation step) of the annulus is well visible. The sporangium was gripped with tweezers (MOV, 20 fps, 832 x 376 pixels, 537 KB).
Poppinga S, Haushahn T, Warnke M, Masselter T, Speck T
CC BY 4.0
<a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4596474/bin/pone.0138495.s007.mov">S6 Video</a> from <cite style="font-style:normal">Poppinga S, Haushahn T, Warnke M, Masselter T, Speck T (2015). "<a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4596474">Sporangium Exposure and Spore Release in the Peruvian Maidenhair Fern (Adiantum peruvianum, Pteridaceae)</a>". <i>PLOS ONE</i>. <a href="https://en.wikipedia.org/wiki/Digital_object_identifier" class="extiw" title="w:Digital object identifier">DOI</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1371/journal.pone.0138495">10.1371/journal.pone.0138495</a>. <a href="https://en.wikipedia.org/wiki/PMID" class="extiw" title="w:PMID">PMID</a> <a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pubmed/26444002">26444002</a>. <a href="https://en.wikipedia.org/wiki/PubMed_Central" class="extiw" title="w:PubMed Central">PMC</a>: <a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4596474">4596474</a>.</cite>