How to theme single node differently to nodes in taxonomy list?
You have access to the $page variable in your template file; if the node is being displayed in a full page this variable will be TRUE, and FALSE otherwise.

If you look at the core node.tpl.php file you can see it too takes advantage of this:

&lt;?php if (!$page): ?&gt;
  &lt;h2&lt;?php print $title_attributes; ?&gt;&gt;&lt;a href="&lt;?php print $node_url; ?&gt;"&gt;&lt;?php print $title; ?&gt;&lt;/a&gt;&lt;/h2&gt;
&lt;?php endif; ?&gt;


That's used to only display a title on the node if it's not the main page display.

You also have access to a $view_mode variable if you want to be more specific about the particular view mode, e.g.:

&lt;?php if ($view_mode == 'teaser'):
&lt;?php // print something ?&gt;
&lt;?php endif; ?&gt;