Archilochus

Archilochus is a genus of hummingbirds. Eastern and western counterparts are the Ruby-throated and Black-chinned.

Description
Diagnostic of the genus are the relatively narrow inner six primaries. Adult males have shield-shaped gorgets with black chins. Females and immatures have mostly plain underparts with little or no buff wash and no rufous in tail. Primary moult typically occurs in September through January.

Separating female and immature Black-chinned Hummingbirds from Ruby-throated Hummingbirds can be difficult (Tyler, 2005), and depends on a detailed study of individual primaries and rectrices (Pyle 1997), as cited in Butler, et al. (2007).

Taxonomy
Some authors consider both to be close to [[Costa's Hummgingbird|Calypte costae.

Species

 * Ruby-throated Hummingbird, Archilochus colubris
 * Black-chinned Hummingbird, Archilochus alexandri