What is "chalcostigma"

Chalcostigma is a genus of hummingbird in the family Trochilidae. The name of the genus is derived from the Greek khalkos meaning bronze and stigme for a spot or mark, a reference to the beard on the bronze-tailed thornbill. It contains the following species:

• Rainbow-bearded thornbill (Chalcostigma herrani)
• Bronze-tailed thornbill (Chalcostigma heteropogon)
• Olivaceous thornbill (Chalcostigma olivaceum)
• Rufous-capped thornbill (Chalcostigma ruficeps)
• Blue-mantled thornbill (Chalcostigma stanleyi)