Family Hummingbirds (Trochilidae)

Least Concern

Blue-tailed Emerald (Chlorostilbon mellisugus)


French: Émeraude orvert German: Blauschwanz-Smaragdkolibri Spanish: Esmeralda coliazul
Other common names: West Andean Emerald (melanorhynchus and pumilus)

Trochilus mellisugus


, 1758,



Formerly considered to include C. auriceps, C. forficatus, C. canivetii, C. assimilis and C. gibsoni, and usually also C. olivaresi, thus comprising some 18 subspecies; conspecific treatment justified because length of tail and depth of tail fork appear to decrease continuously from N to S, while red-billed forms appear in both N and S groups; moreover, the different forms replace each other geographically, their ranges meeting. However, one alternative, on basis of bill colour, is to treat the five N forms (auriceps, forficatus, canivetii, osberti and salvini) as one species, assimilis as another, gibsoni (with chrysogaster and nitens) as a third, and remaining S races in C. mellisugus as a fourth; this arrangement has at times been varied with the lumping of assimilis in the mellisugus group, or a transfer of melanorhynchus (including pumilus) to the gibsoni group. A more radical evaluation of the complex is largely followed here#R, but, owing to both the sheer number of taxa in the original complex and the diaspora of specimen material, comparisons between taxa and decisions on their taxonomic status herein are limited mainly to geographical neighbours. Western form melanorhynchus, with race pumilus, may also be separated on account of its all-black bill, moderately forked tail, glittering crown, breast with little or no blue, and female with trace of grey in outer rectrices and extensive green in central rectrices, but split not followed herein, as these characters differ little from those of other E and S forms of C. mellisugus, whose remaining races are characterized by black bill, glittering crown, breast with blue tinge, tail shallowly forked, female tail blue with trace of dusky on lateral rectrices. Several of presently accepted races may be invalid; further study required, especially in zones of possible contact. Proposed race nanus of upper and middle Orinoco, at one stage placed in canivetii group, may be best considered a synonym of caribaeus. Form napensis (= vitticeps), of R Napo in E Ecuador, indistinguishable from phoeopygus. Species formerly known as C. prasinus, when name mellisugus was erroneously thought to apply to Amazilia (Saucerottia) saucerottei braccata. Eight subspecies currently recognized.

Subspecies and Distribution
  • C. m. pumilus Gould, 1872 – arid and semi-arid tropical and subtropical zones of W Colombia and W Ecuador.
  • C. m. melanorhynchus Gould, 1860 – Western Emerald – upper subtropical W Colombia into temperate zone in W & C Andes of Ecuador.
  • C. m. caribaeus Lawrence, 1871 – islands of Aruba, Curaçao, Bonaire, Trinidad and Margarita, and NE Venezuela.
  • C. m. duidae J. T. Zimmer & Phelps, Sr, 1952 – Mt Duida, in S Venezuela (Amazonas).
  • C. m. subfurcatus Berlepsch, 1887 – E & S Venezuela, Guyana and R Branco region of NW Brazil.
  • C. m. mellisugus (Linnaeus, 1758) – Blue-tailed Emerald – Suriname, French Guiana, and lower Amazon of NE Brazil.
  • C. m. phoeopygus (Tschudi, 1844) – upper Amazon and its E tributaries in Colombia, Ecuador and Peru.
  • C. m. peruanus Gould, 1861 – SE Peru, N & E Bolivia and W Brazil.
  • Descriptive notes

    Male 7·5–9·5 cm, female 6·5–7·5 cm; 2·3–3·5 g. Male has short, straight bill (1·3–1·8 cm),... read more


    Song a continuous series of subdued scratchy and wheezy notes, at a rate of 3–4 notes/second,... read more


    From tropical to temperate zone, mainly between 750 and 2600 m in Ecuador (phoeopygus) and... read more

    Food and feeding

    Usually feeds low down on nectar of flowering Hibiscus, Lantana, Sesanum indicum and Cannaceae, sometimes taking... read more


    Jan–Jun in W & C Andes; at two different localities in NC Venezuela, nesting behaviour observed in Jan–Jun, Aug, Sep, Nov... read more


    Sedentary, with some seasonal altitudinal dispersal after breeding (perhaps only reaching temperate... read more

    Status and conservation

    Not globally threatened (Least Concern). CITES II. Readily accepts man-made habitat. Generally considered to be common throughout much of its extensive range, e.g. in upper... read more

    Recommended citation

    Bündgen, R., Kirwan, G.M. & Boesman, P. (2020). Blue-tailed Emerald (Chlorostilbon mellisugus). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from on 23 January 2020).