Appearance

Scaled Ground-Cuckoo is a large terrestrial cuckoo (about 43 cm in length) that is reminiscent of Greater Roadrunner (Geococcyx californianus) of the American Southwest and Mexico in general shape and behavior. As such, it has a large, sharply-ridged bill, a prominent crest that is frequently raised and lowered, a long tail, and strong tarsi and toes. Scaled Ground-Cuckoo, however, is much more brightly colored with its shiny blue-black crest, bronzy brown back and wing coverts, and dark wings glossed with green and purple. Much of its underparts, rump, and upper tail coverts are rufous brown. The breast feathers are buff or grayish marked with dark semicircular bands giving a scaled appearance, and it has an indistinct breast band. The iris is bright red, bordered behind with cobalt blue skin.

There are five species of Neomorphus ground-cuckoos in the Neotropics, but they replace one another geographically so that only one species generally inhabits a given forest region. Also the species of Neomorphus differ to some degree in the color and patterning of their anterior underparts and upperparts, and in the color of the bill and bare orbital skin (Haffer 1977).

Scaled Ground-Cuckoo is very similar in appearance to Rufous-vented Ground-Cuckoo (N. geoffroyi). and has been considered to be a subspecies of N. geoffroyi by several authors (e.g., Haffer 1977, Pinto 1964, Payne 1997, 2005). The prospective geographic distributions of these cuckoos are adjacent to one another in the lower Rio Tapajós area in Brazil south of the Amazon River (Payne 2005). However, other authors have maintained that Scaled Ground-Cuckoo can be separated from Rufous-vented Ground-Cuckoo by aspects of its plumage, including a rudimentary or absent breast band and unmarked cinnamon-buff ear-coverts and malar region, rather than the prominent black breast band and barred ear-coverts and malar region that characterize the nearest populations of Rufous-vented Ground-Cuckoo (N. g. amazonicus; Firme et al. 2014). See Systematics: Related Species.

Adult: Sexes similar. Forehead and crown brownish with buffy margins; prominent glossy purplish blue crest. Auriculars and malar regions unmarked cinnamon buff. Hind neck, upper back, and wing coverts bronzy olive brown; lower back and scapulars bronzy brown to purplish, grading to deep purplish brown glossed with bronze on rump and uppertail coverts. Wings olive green with darker, more bluish primaries that are glossed with purple. Throat dusky white or pale buff; breast feathers buff or grayish marked with bold dark semicircular bands giving a scaled appearance. Black breast band indistinct. Underparts whitish or buffy deepening to chestnut on flanks, lower belly, and undertail coverts. Tail black glossed with purple and green above.

Juvenile: Upperparts similar to adult, except forehead dark brown and unscaled. Breast and flanks uniform dark brown; belly dark brown with paler center. Tail shorter than adult.

Nestling: Undescribed.

These descriptions are from Todd (1925), Haffer (1977), Erritzøe et al. (2012), and Firme et al. (2014).

Little information. Scaled Ground-Cuckoo presumably follows the Complex Basic molt strategy. There is no information on timing of molt in this species, except single observation of a juvenile molting its underparts in March (Erritzøe et al. 2012).

Iris: cherry red

Facial skin: area behind eye bare, with bright cobalt blue skin

Bill: greenish with yellowish tip and paler, bluish dusky base

Tarsi and toes: slate gray

Bare parts descriptions from Todd (1925) and Erritzøe et al. (2012).

Total length: 43 cm (Erritzøe et al. 2012).

Linear measurements, male (from Payne 2005):

wing length: mean 166 mm (range 163-171, n = 3)

Linear measurements, female (from Payne 2005)

wing length: mean 165 mm (range 160-170, n = 2)

Linear measurements, sex unknown (from Todd 1925, Pinto 1964):

wing length: 160-161 mm

tail length: 270 mm

culmen length: 42-45 mm

tarsus length: 65-66 mm

Mass, male: 340 g, n = 1 (Graves and Zusi 1990)