diff --git a/ippisite/ippidb/models.py b/ippisite/ippidb/models.py
index 3fb6dd3239e1601eeb15da16d36ea68f3da3390e..ee7d95a9f1dac4426eb94d77142eb7fdfe76c795 100644
--- a/ippisite/ippidb/models.py
+++ b/ippisite/ippidb/models.py
@@ -50,7 +50,7 @@ class BibliographyForm(ModelForm):
         exclude = ['title','journal_name', 'authors_list', 'biblio_year']
 
 class Taxonomy(models.Model):
-    taxonomy_id = models.DecimalField('NCBI TaxID', unique=True, max_digits=4, decimal_places=0)
+    taxonomy_id = models.DecimalField('NCBI TaxID', unique=True, max_digits=9, decimal_places=0)
     name = models.CharField('Organism name', max_length=200)
     class Meta:
         verbose_name_plural = "taxonomies"