I'm receiving the following errors in Google's Structured Data Testing Tool:
It seems like the page for the category "galeria" does not contain these fields. There are also some more errors like this (all with categories links). The strange thing is that the first category doesn't show those errors.
Anyway, I added the "entry-title" fields:
<section class="content">
<div class="page-title pad group">
<h1 class="entry-title"><i class="fa fa-folder-open"></i>Categoría <span>Biología</span></h1>
</div>
...
</section>
but the error is still there.
Also, "author" and "update" doesn't seem to make sense here (categories), so should those messages be ignored?
Update:
Here is a link to Google's Structured Data Testing Tool for the page to demonstrate this, and to view the HTML code by clicking on the HTML tab.