Editing Ruby-crowned kinglet (section)

{{Short description|Species of bird}}
{{Speciesbox
| status = LC
| status_system = IUCN3.1
| status_ref = <ref name=IUCN>{{cite iucn |author=BirdLife International |year=2021 |title=''Regulus calendula'' |page=e.T22712567A137575998 |doi=10.2305/IUCN.UK.2021-3.RLTS.T22712567A137575998.en |access-date=27 November 2022}}</ref>
| image = Regulus calendula MP 3.jpg
| image_caption = Male in Réserve naturelle du Marais-Léon-Provancher, Québec, Canada
| image2 = Ruby-crowned kinglet in Green-Wood Cemetery (55761).jpg
| image2_caption = Female in New York, USA
| taxon = Corthylio calendula
| parent_authority = [[Jean Cabanis|Cabanis]], 1853
| authority = ([[Carl Linnaeus|Linnaeus]], 1766)
| range_map =Corthylio calendula map.svg
| range_map_caption= Range of ''C. calendula''
{{leftlegend|#8d5fd3|outline=gray|Year round}}{{leftlegend|#ff9955|outline=gray|Summer (breeding)}}{{leftlegend|#87aade|outline=gray|Winter (nonbreeding)}}{{leftlegend|#ffdd55|outline=gray|Migration}}
<small>(ranges are approximate)</small>
| synonyms = ''Regulus calendula'' {{small|Linnaeus,&nbsp;1766}}
}}

The '''ruby-crowned kinglet''' ('''''Corthylio calendula''''') is a very small [[passerine]] bird found throughout [[North America]]. It is a member of the [[kinglet]] family. The bird has olive-green plumage with two white wing bars and a white eye-ring. Males have a red crown patch, which is often concealed. The sexes are identical apart from the crown, and juveniles are similar in plumage to adult females. It is one of the smallest songbirds in North America. The ruby-crowned kinglet is not closely related to other kinglets and was moved from ''[[Regulus (bird)|Regulus]]'' to its own [[genus]], ''Corthylio'' in 2021.<ref name=":0" /> Three [[subspecies]] are currently recognized.

The kinglet is mostly migratory, and its range extends from northwest Canada and Alaska south to Mexico. Its breeding habitat is [[spruce-fir forests]] in the northern and [[mountain]]ous regions of the United States and Canada. The ruby-crowned kinglet builds a cup-shaped [[bird nest|nest]], which may be pensile or placed on a tree branch and is often hidden. It lays up to 12 eggs, and has the largest clutch of any North American passerine for its size. It is mainly [[insectivorous]], but also eats fruits and seeds.