Acordding to Google Support I have a site wiht the same configuration, but only for spanish and english:
<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"
xmlns:xhtml="http://www.w3.org/1999/xhtml">
<url>
<loc>http://example.com/en/</loc>
<xhtml:link
rel="alternate"
hreflang="es"
href="http://example.com/es/"
/>
<xhtml:link
rel="alternate"
hreflang="en"
href="http://example.com/en/"
/>
<changefreq>daily</changefreq>
<lastmod>2015-07-19</lastmod>
<priority>1</priority>
</url>
<url>
<loc>http://example.com/es/</loc>
<xhtml:link
rel="alternate"
hreflang="en"
href="http://example.com/en/"
/>
<xhtml:link
rel="alternate"
hreflang="es"
href="http://example.com/es/"
/>
<changefreq>daily</changefreq>
<lastmod>2015-07-19</lastmod>
<priority>1</priority>
</url>
<url>
<loc>http://example.com/en/blog</loc>
<xhtml:link
rel="alternate"
hreflang="es"
href="http://example.com/es/blog"
/>
<xhtml:link
rel="alternate"
hreflang="en"
href="http://example.com/en/"
/>
<changefreq>daily</changefreq>
<lastmod>2015-07-19</lastmod>
<priority>0.8</priority>
</url>
<url>
<loc>http://example.com/es/blog</loc>
<xhtml:link
rel="alternate"
hreflang="en"
href="http://example.com/en/blog"
/>
<xhtml:link
rel="alternate"
hreflang="es"
href="http://example.com/es/blog"
/>
<changefreq>daily</changefreq>
<lastmod>2015-07-19</lastmod>
<priority>0.8</priority>
</url>
</urlset>
My problem is when I search my site using a Browser on spanish, because my site appears, but the description of the site is in English. I pressume that my sitemap is missing something. Anyone knows why Googles doesn't consider the spanish version?