This is a mature female <i><a href="//commons.wikimedia.org/wiki/Latrodectus_katipo" title="Latrodectus katipo">Latrodectus katipo</a></i>, found living under driftwood at Himatangi Beach, Manawatu, New Zealand.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/27388205@N00">jesscostall</a>
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<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/27388205@N00/80496338/">female Latrodectus katipo</a>