Purple-crowned Plovercrest

The purple-crowned plovercrest, or violet-crowned plovercrest, (Stephanoxis loddigesii) is a species of hummingbird in the "emeralds", tribe Trochilini of subfamily Trochilinae. It is found in Argentina, Brazil, and Paraguay. == Taxonomy and systematics == The purple-crowned plovercrest and green-crowned plovercrest (Stephanoxis lalandi) were originally treated as separate species but in the mid-1900s were combined under the name "plovercrest" with the binomial S. lalandi. A study published in 2014 provided evidence that the original two-species treatment was correct. Taxonomists worldwide agreed and the two taxa were restored to species status. They are the only members of the genus and are monotypic. == Description == The purple-crowned plovercrest is 8.5 to 9.5 cm (3.3 to 3.7 in) long. Males weigh about 3.7 g (0.13 oz). Both sexes have a shortish, straight, black bill. Adult males have a shaggy violet-blue crest. Their face, chin, and throat are brownish with a white spot behind the eye. Their upperparts yellowish green. Their lower throat to upper belly is blackish violet-blue and the rest of the underparts are gray. Their central two pairs of tail feathers are green and the rest green with a blackish band near the end and whitish tips. Adult females and juveniles…