This is what I see in your robots.txt file:
#Begin Attracta SEO Tools Sitemap. Do not remove
sitemap: http://cdn.attracta.com/sitemap/2921366.xml.gz
#End Attracta SEO Tools Sitemap. Do not remove
I don't see anything that would cause the SEOmoz crawler to act weirdly.
On another note, have you considered hosting the sitemap on your own domain instead of through that SEO plugin's CDN?
Have you submitted a sitemap to Google Webmaster Tools? Do you have Indexation stats in GWT?
In that sitemap, I see you have lines like:
<loc>http://www.animhut.com/tag/rare/</loc>
You should probably elect to prevent tags from appearing in the sitemap, as those pages are just duplicate content. I'm not sure which SEO plugin or Sitemap generator plugin you are using, but some of them have the ability to block certain post types / categories archives / tags, etc from appearing in the sitemap.
Anyways... this all might not be of interest to you, but I figured since I was looking at your site, I'd write down my observations while I'm at it.
Scott O.