Purple-backed Thornbill

Colombia

Jul 17

Purple-backed Thornbill (Ramphomicron microrhynchum)

Name Origin:
The genus Ramphomicron combines Greek rhamphos meaning “bill” and mikron meaning “small,” referring to its very short, fine bill. The species name microrhynchum also highlights the tiny beak, reinforcing its defining morphology.

Quick Facts

🪶 Length: 7.5–9 cm (3.0–3.5 in)
⚖️ Weight: ~2.5–3 g (0.09–0.11 oz)
🌎 Range: Andes from Venezuela south to Bolivia
🧭 Elevation: 2,800–4,000 m
🌸 Diet: Nectar and small insects
🏡 Habitat: High-elevation elfin forest, páramo edges, and shrubby slopes
🧬 Clade: Lesbiini (a.k.a. “coquettes”)
📊 Status: Least Concern (IUCN 2024)

Subspecies & Distribution

Four subspecies:

Ramphomicron microrhynchum andicola
Distribution: Andes of Venezuela (Mérida)
Ramphomicron microrhynchum microrhynchum
Distribution: Andes of Colombia, Ecuador, and northwestern Peru (south to Cajamarca)
Ramphomicron microrhynchum albiventre
Distribution: Eastern slopes of central and southern Peru (Huánuco to Cusco and Apurímac)
Ramphomicron microrhynchum bolivianum
Distribution: Andes of central Bolivia (Cochabamba)

Species Overview

The Purple-backed Thornbill is a tiny high-elevation hummingbird with a distinctive shape and short bill. Males have a deep iridescent violet back and crown with a shining green gorget and blackish underparts. Females are more subdued, with white-spotted underparts and bronzy upperparts. This species is specialized for cooler, high-mountain habitats and is often solitary, darting among flowering shrubs in windswept páramo margins.

Male Description:
Violet-purple crown and back, glittering green throat, dark underparts, and a short straight bill. The tail is slightly forked and dark with subtle gloss. Compact and agile in flight.

Female Description:
Greenish-bronze upperparts, pale belly with green spots or streaks, short dark tail with pale tips. Lacks the iridescent crown and gorget. Slightly smaller in appearance due to less flaring plumage.

Habitat & Behavior:
Inhabits elfin forest edges, high-elevation shrublands, and páramo transition zones. Forages on nectar from low flowering shrubs and small trees, sometimes capturing insects midair. Known for brief, darting flights and hovering low near the ground. May perch inconspicuously in dense vegetation. Rarely vocal.

Conservation Note:
Though restricted to high elevations, the species is widely distributed along the Andes and is not currently facing significant threats. Its preference for less-accessible habitats and some occurrence in protected areas helps buffer it against development. However, páramo degradation and shifting climatic zones remain long-term concerns.

Below is the Purple-backed Thornbill (Ramphomicron microrhynchum microrhynchum)

Photographed at Hotel Termales del Ruíz, Caldas, and PNN Chingaza–Entrada Piedras Gordas, Cundinamarca, Colombia

These individuals belong to the subspecies microrhynchum, found along the Andes from Colombia through Ecuador into northwestern Peru. It occupies elfin forest and páramo edge between 3,000 and 4,000 meters. This form is characterized by its small body size, metallic violet crown and back, and extremely short bill. Males show a green gorget contrasting sharply with their dark underparts.