Southern Emerald-Toucanet Aulacorhynchus albivitta

  • Order: Piciformes
  • Family: Ramphastidae
  • Polytypic: 7 subspecies
  • Authors: Thomas S. Schulenberg, A. M. Contreras-González, Claudia I. Rodríguez-Flores, Carlos A. Soberanes-González, Marîa del Coro Arizmendi, and Kolten Powell
Sections

Appearance

Distinguishing Characteristics

Aulacorhynchus toucanets are small to medium-sized, green toucans. Southern Emerald-Toucanet is a small Aulacorhynchus, with a total length of 30-37 cm. The body primarily is emerald green, with chestnut undertail coverts and tips to the rectrices. The color of the throat varies geographically: it may be white, pale gray, blue, or black. The bill is long and laterally compressed, and is mostly black, but the maxilla is yellow; the extent of yellow is another feature that varies geographically, and in some populations is restricted to the tip of the culmen.

Similar Species

In the Andes, from Venezuela south of Bolivia, Southern Emerald-Toucanet overlaps geographically with several other species of Aulacorhynchus. Only one of these, Groove-billed Toucanet (Aulacorhynchus sulcatus), is likely to be source of confusion in the field. One subspecies of Groove-billed, calorhynchus, overlaps geographically with the emerald-toucanet, and also has an extensive area of yellow on the bill; in fact, this population sometimes is recognized as a separate species, "Yellow-billed Toucanet". "Yellow-billed" and Southern Emerald-Toucanet overlap in the Sierra Nevada de Santa Marta in northern Colombia, in the Sierra de Perijá along the Colombia/Venezuela border, and in the Andes of northwestern Venezuela. "Yellow-billed Toucanet" differs from the emerald-toucanet by lacking chestnut on the undertail coverts and the tips to the rectrices. Furthermore, the "Yellow-billed Toucanet" always has more yellow on the bill than do the sympatric subspecies of Emerald Toucanet, with yellow not only on the maxilla, but also on the base and tip of the mandible. The subspecies of emerald-toucanet that occurs in the Sierra Nevada de Santa Marta, lautus, has even less yellow on the bill, with yellow restricted to the culmen.

The emerald-toucanet readily is distinguished by bill color from other members of the genus, all of which lack lack yellow on the bill. Additionally, Crimson-rumped Toucanet (Aulacorhynchus haematopygus) of the northern Andes, Yellow-browed Toucanet (Aulacorhynchus huallagae) of northern Peru, and Blue-banded Toucanet (Aulacorhynchus coeruleicinctis) of the southern Andes all are larger than the emerald-toucanet, typically occur at higher elevations, and have a bright red rump patch.

There is unlikely to be any contact between the southernmost population of Northern Emerald-Toucanet (Aulacorhynchus prasinus), along the Panama/Colombia border, and the nearest population of Southern Emerald-Toucanet of the Andes of Colombia. In any event, the throat of this population of Southern Emerald-Toucanet (subspecies griseigularis) is pale gray, not deep blue as in the southernmost population of Northern Emerald-Toucanet (subspecies cognatus).

Detailed Description

The following description is based on Short and Horne (2001), and refers to nominate albivitta; see also Geographic Variation:

Adult: Sexes similar. Mainly green, tinged bronzy on the crown and forecrown, and with a yellowy bronze tint on the upper back. Small blue mark above and at rear of eye. Underparts paler than the upperparts. The rectrices are deep blue distally, with broad chestnut tips (chestnut tips narrower, or occasionally lacking, on the central pair). Chin, throat, and malar white, grading into the green on the breast. Flanks bright yellow-green to green-yellow. Undertail coverts chestnut.

Immature: Similar to adult, but feathers duller (grayer, less yellow). Rectrices more pointed, with reduced chestnut tips, and the chestnut is browner and duller.

Bare Parts

Orbital skin: yellow to orange

Iris: gray-brown to brown or chestnut

Bill: Shape typical of toucans: long, with a curved culmen, and serrated along tomia. Generally the maxilla is extensively yellow and the mandible is black, but there is considerable variation in pattern across subspecies; see Geographic Variation. In nominate albivitta, the maxilla is mostly yellow, and the mandible is mostly black. The base of the bill, in a narrow vertical stripe that extends downward from the nares, is white. There is a chestnut patch at the base of the mandible.

Tarsi and toes: olive-green; soles dusky yellow or ochraceous

Bare parts color data from Short and Horne (2001).

Measurements

Total length: 33 cm (Hilty and Brown 1986), 33-34 cm (Ridgely and Greenfield 2001b), 38 cm (Hilty 2003)

Linear measurements:

Mensural data (mm) for Aulacorhynchus prasinus (Short and Horne 2001). Males are larger in all dimensions, but the difference in bill length is particularly pronounced
subspecies sex wing tail bill tarsus
lautus male mean (n) 127.6 (19)
range 122-133
female mean (n) 125.1 (14)
range 117-131
albivitta male mean (n) 131.1 (43)
range 121-143
female mean (n) 128.1 (31)
range 118-139
griseigularis male mean (n) 126.7 (13)
range 123-134
female mean (n) 125.9 (17)
range 118-135
phaeolaemus male mean (n) 130.1 (25)
range 122-138
female mean (n) 126.0 (8)
range 122-129
cyanolaemus male mean (n) 127.7 (22)
range 114-135
female mean (n) 126.6 (18)
range 123-134
atrogularis male mean (n) 125.0 (15)
range 118-131
female mean (n) 122.7 (12)
range 118-133
dimidiatus male mean (n) ------ (3)
range 109-118
female male (n) 112.7 (10)
range 106-117

Other important sources of morphometric data for Southern Emerald-Toucanet Haffer (1974), and Winker (2000, 2016).

Mass: Data (g) from Short and Horne (2001):

albivitta, male: mean 195.4 (range 160-230, n = 5)

female: mean 183.1 (range 170-205, n = 8)

phaeolaemus, male: 199, 203 (n = 2)

cyanolaemus, male: mean 176.6 (range 160-210, n = 5)

female: mean 158.8 (range 130-210, n = 5)

atrogularis, male: mean 163.4 (range 124-188, n = 9)

female: mean 147.6 (range 124-200, n = 8)

dimidiatus, male: range 127-132 (n = 3)

female: 110, 115 g (n = 2)

Recommended Citation

Schulenberg, T. S., A. M. Contreras-González, C. I. Rodríguez-Flores, C. A. Soberanes-González, M. d. C. Arizmendi, and K. Powell (2017). Southern Emerald-Toucanet (Aulacorhynchus albivitta), version 1.0. In Neotropical Birds Online (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/nb.souemt1.01