query: # Find Acacias without an image
  SELECT ?item ?itemLabel?taxon_name ?image  WHERE {
  SERVICE wikibase:label { bd:serviceParam wikibase:language "en". }
      ?item wdt:P225 ?taxon_name.
      ?item wdt:P171 wd:Q81666.   # whose genus is Acacia
    MINUS
    {?item wdt:P18 ?image.
    }
  }
  ORDER BY ?itemLabel ?item ?taxon_name 
  