Flame-rumped Sapphire (Hylocharis pyropygia)
The enigmatic Flame-rumped Sapphire was described in 1881, it is thought to originate from Brazil, however, according to the original description it doesn’t.:
“This is also one of Mr. Whitely’s recent discoveries, he having found it in company with a number of well-known Ecuador species of Humming- and other birds; so that it is reasonable to suppose it came from that country.” [1]
The Flame-rumped Sapphire might well be an now extinct species, however, it is now widely believed to be a hybrid of two other hummingbird species, the Glittering-bellied Emerald (Chlorostilbon lucidus (Shaw)) and the White-chinned Sapphire (Hylocharis cyanus Vieillot); I have included it here for the sake of completeness.
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References:
[1] Osbert Salvin; F. D. Godman: On some new and little-known species of Trochilidae. The Ibis 4(5): 595-597. 1881
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(public domain)
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edited: 03.11.2020