Species (5)
'species' is the definition.
(thesaurus)
This is all the clue.
(Other definitions for genus that I've seen before include "Taxonomic group (biol.)" , "species grouped together" , "Category between family and species" , "Taxonomic grouping" , "Biological group containing one or more species" .)
(Other definitions for endangered that I've seen before include "Vulnerable" , "in a perilous situation" , "put at risk" , "Like some species" , "Put in jeopardy" .)