Why don't i have any result?

Why this query doens't return any result with jena and with protege does??
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX owl: <http://www.w3.org/2002/07/owl#>
SELECT ?equivalentClass
WHERE {
?equivalentClass owl:equivalentClass ?Class .
?Class rdfs:label "champinhons" }


<owl:Class rdf:about="#Champinhon">
<rdfs:subClassOf rdf:resource="#Plant"/>
<owl:equivalentClass rdf:resource="#Mushroom"/>
<rdfs:label rdf:datatype="http://www.w3.org/2001/XMLSchema#string
">champinhons</rdfs:label>
<rdfs:label rdf:datatype="http://www.w3.org/2001/XMLSchema#string
">champinhon</rdfs:label>
</owl:Class>

<owl:Class rdf:ID="Cogumelo">
<rdfs:subClassOf>
<owl:Class rdf:ID="Planta"/>
</rdfs:subClassOf>
<owl:equivalentClass>
<owl:Class rdf:ID="Champinhon"/>
</owl:equivalentClass>
<rdfs:label rdf:datatype="http://www.w3.org/2001/XMLSchema#string
">cogumelo</rdfs:label>
</owl:Class>