Blue-black grassquit
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The blue-black grassquit (Volatinia jacarina) is a small Neotropical bird in the tanager family, Thraupidae. It is the only member of the genus Volatinia. It is a common and widespread bird that breeds from southern Mexico through Central America, and South America as far as northern Chile, Argentina, and Paraguay, and in Trinidad and Tobago.<ref>Template:Cite journal</ref> A male was also observed in Graham County, Arizona on July 15 and July 17, 2023.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
This species is sexually dimorphic; the male is glossy blue with some white under the wing. The female is brown above and pale buff with darker streaks below.
TaxonomyEdit
The blue-black grassquit was described by the Swedish naturalist Carl Linnaeus in 1766 in the twelfth edition of his Systema Naturae under the binomial name Tanagra jacarina.<ref>Template:Cite book</ref> Linnaeus based his description on the "Jacarni" that was described in 1648 by the German naturalist Georg Marcgrave in his Historia Naturalis Brasiliae.<ref>Template:Cite book</ref><ref name="paynter">Template:Cite book</ref> The type locality is eastern Brazil.<ref name=paynter/> The specific epithet jacarina is derived from the Tupi language and was used for a type of finch.<ref>Template:Cite book</ref> The blue-black grassquit is now the only species placed in the genus Volatinia and was introduced in 1850 by the German naturalist Ludwig Reichenbach.<ref>Template:Cite book</ref><ref name="ioc">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> The genus name is a diminutive of the Latin volatus meaning "flying".<ref>Template:Cite book</ref>
Within the tanager family Thraupidae the blue-black grassquit is in the subfamily Tachyphoninae and is a member of a clade that contains the genera Conothraupis and Creurgops.<ref name="burns2014">Template:Cite journal</ref><ref>Template:Cite journal</ref>
The blue-black grassquit was formerly placed with the buntings in the subfamily Emberizinae rather than with the tanagers in Thraupinae within an expanded family Emberizidae.<ref name=paynter/><ref name=burns2014/>
Three subspecies are recognised:<ref name=ioc/>
- V. j. splendens (Vieillot, 1817) – Mexico to Colombia and east through Venezuela and the Guianas to the Amazon basin; also Trinidad, Tobago and Grenada
- V. j. jacarina (Linnaeus, 1766) – southeast Peru to east Brazil and south to north Argentina
- V. j. peruviensis (Peale, 1849) – west Ecuador, west Peru, and northwest Chile
DescriptionEdit
Adult blue-black grassquits are Template:Convert long and weigh Template:Convert. They have a slender conical black bill. The male is glossy blue-black, with a black tail and wings; the white inner underwing is visible in flight or display. Female and immature birds have brown upperparts and dark-streaked buff underparts.
BehaviorEdit
Social monogamous, extra-pair fertilizations, intraspecific parasitism, and quasi-parasitism are commonly found.<ref>Template:Cite journal</ref><ref>Template:Cite journal</ref> During the breeding season, males defend small territories, about 13,0 - 72,5 m2, dominant males are normally lighter.<ref>Template:Cite journal</ref> The male has a jumping display, often performed for long periods, which gives rise to the local name "johnny jump-up". This is accompanied by a persistent wheezing jweeee call,<ref>Template:Cite journal</ref> jumping several times in a minute.<ref>Template:CitationTemplate:Cbignore</ref> The extravagant display also has a cost of calling attention of the predator, thus displaying increased nest predation.<ref>Template:Cite journal</ref> Predation is the main cause of breeding failure,<ref name=":0">Template:Cite journal</ref> and predator vocalizations can cause an immune-related reaction to this species.<ref>Template:Cite journal</ref> Nests are small cups of rootlets (diameter about 7.5 cm) found in herbaceous vegetation 10–50 cm high,<ref>Template:Cite journal</ref> clustered at a landscape,<ref>Template:Cite journal</ref> and placed preferably at high complex habitat spots.<ref>Template:Cite journal</ref> Nests are built by both sexes.<ref name=":0" /><ref>Template:CitationTemplate:Cbignore</ref>
Blue-black grassquits will often form flocks when not breeding. They eat seeds, mostly on the ground.<ref>Template:Cite book</ref>