diff --git a/python/obitools3/dms/taxo/taxo.pyx b/python/obitools3/dms/taxo/taxo.pyx
index a5894f2..758b7ac 100644
--- a/python/obitools3/dms/taxo/taxo.pyx
+++ b/python/obitools3/dms/taxo/taxo.pyx
@@ -110,7 +110,7 @@ cdef class Taxonomy(OBIWrapper) :
         if type(ref) == int :
             return self.get_taxon_by_taxid(ref)
         else :
-            raise Exception("Not implemented")
+            raise NotImplementedError()
 
 
     cpdef Taxon get_taxon_by_taxid(self, int taxid):   # TODO check deleted taxon behavior (403122)
diff --git a/python/obitools3/parsers/fasta.pyx b/python/obitools3/parsers/fasta.pyx
index fd169d9..e052851 100644
--- a/python/obitools3/parsers/fasta.pyx
+++ b/python/obitools3/parsers/fasta.pyx
@@ -101,7 +101,7 @@ def fastaNucIterator(lineiterator,
     cdef dict       tags
     cdef list       s
     cdef bytes      sequence
-    cdef int        lines_to_skip, ionly, read
+    cdef int        skipped, ionly, read
     cdef Nuc_Seq    seq
     
     if only is None: