Scientific and common names in SKOS

Dear all,

I have the following problem: how to represent a KOS which contains organisms
with scientific names and common names in SKOS?

example for plants:  potatoes and "Solanum tuberosum", will these be 2
skos:concepts? NOTE: they may be both descriptors in the KOS, for indexing
purposes. 
Both can have multiple non-descriptors...

<skos:Concept rdf:about="http://www.fao.org/aims/aos/agrovoc#potatoes">
    <skos:prefLabel xml:lang="en">potatoes</skos:prefLabel>
</skos:Concept>

<skos:Concept
rdf:about="http://www.fao.org/aims/aos/agrovoc#Solanum_tuberosum">
    <skos:prefLabel xml:lang="en">Solanum tuberosum</skos:prefLabel>
    <skos:exactMatch
rdf:resource="http://www.fao.org/aims/aos/agrovoc#potatoes"/>
</skos:Concept>

OR

<skos:Concept rdf:about="http://www.fao.org/aims/aos/agrovoc#potatoes">
    <skos:prefLabel xml:lang="en">potatoes</skos:prefLabel>
</skos:Concept>

<skos:Concept
rdf:about="http://www.fao.org/aims/aos/agrovoc#Solanum_tuberosum">
    <skos:prefLabel xml:lang="LA">Solanum tuberosum</skos:prefLabel>
    <skos:exactMatch
rdf:resource="http://www.fao.org/aims/aos/agrovoc#potatoes"/>
</skos:Concept>

OR

<skos:Concept rdf:about="http://www.fao.org/aims/aos/agrovoc#potatoes">
    <skos:prefLabel xml:lang="en">potatoes</skos:prefLabel>
    <skos:prefLabel xml:lang="LA">Solanum tuberosum</skos:prefLabel>
</skos:Concept>

What if in the terminology i use both scientific name and common name are
preferred and they are both marked in English? ... i cannot use 2
skos:prefLabel  for same language...

Thanks

Margherita