Purple-throated Mountain-gem (Lampornis caloaemus); Colibrí Montañés Gorgimorado; Purpurkehlnymphe; Colibri à gorge pourprée

For only the second time in all these years I recorded a Purple-throated Mountain-gem at our house in San Antonio. The bird stayed in the same area of the garden each day from 11 May until at least 14 May. Its scarcity in my garden is very surprising since, firstly, the species is a common inhabitant of the middle elevations on the Turrialba Volcano slope. In addition, however, it is also well-known that beginning in May some birds of this species move to lower elevations in the post-breeding season. The female below perched repeatedly at the exact same location. My apologies, but this is the best photo I could get with my cellphone:

My only previous record here at the house was in July 2021 when a single male stayed in the garden from between at least the 24th to the 30th of that month. No photographs were taken on that occasion. Identification – never really in doubt – was made on the basis of the male’s purple throat and turquoise forecrown. I am very familiar with this species since it is so common higher up on the Turrialba Volcano slope.

However, a quick check of the field guides raises several questions concerning Lampornis hummingbirds. The other possibilities for our area are assumed to be 1) the White-throated Mountain-gem (Lampornis castaneoventris) – the female of which is almost identical to the female Purple-throated, hence the Latin name castaneoventris – and 2) the White-bellied Mountain-gem (Lampornis hemileucus). But for neither of these two species can I find photographic evidence from the Cartago Province side (our side) of the Turrialba Volcano slope.

Principally then, my own concern is with the difficulty in distinguishing between the female Purple-throated and the female White-throated. Without further evidence, however, I continue to assume that any Lampornis species reported on the Turrialba Volcano slope is Lampornis caloaemus, the Purple-throated Mountain-gem. Any photographs taken of other Lampornis species in the Turrialba area will be most welcome additions to this post for purposes of comparison.