query: SELECT ?item ?taxonName ?itemDesc WHERE {
     ?item wdt:P225 ?taxonName .
     ?item wdt:P105 wd:Q7432 . # species
     ?item (wdt:P171)* wd:Q5113 . # Aves
     SERVICE wikibase:label {
     bd:serviceParam wikibase:language "cy" .
     ?item schema:description ?itemDesc .
     }
     #FILTER( !bound( ?itemDesc ) )
     FILTER(!regex(?itemDesc, "rhywogaeth o adar"))
  }
  ORDER BY ASC(?taxonName)