Choco Poorwill is a small (19-21 mm) dark brown nightjar. This poorwill has a large white throat patch. There are no white bands on the remiges, but there are two or three promientt white spots on the wing coverts, and all of the rectrices have narrow white tips. The sexes of Choco Poorwill are similar.
Choco Poorwill is similar to Ocellated Poorwill (Nyctiphrynus ocellatus), and formerly was classified as a subspecies of Ocellated. These two species are allopatric, and have different vocalizations. Additionally, the sexes are similar in Choco Poorwill, but Ocellated Poorwill is sexually dimorphic; Choco Poorwill lacks the bold white spots on the lower breast and belly of Ocellated; Ocellated lacks the white spots on the wing coverts of Choco; and Ocellated has broader white tips to the rectrices, although these tips are restricted to the outer pairs. Common Pauraque (Nyctidromus albicollis) is larger and longer tailed, with cinnamon rufous auriculars; male pauraque also has a white band on the outer remiges, and prominent white stripes on the tail.
The following description is based on Cleere (1998):
Adult: Sexes similar in plumage. Dark cinnamon brown overall with blackish brown spotting. Forecrown, crown, and nape and crown grayish brown, heavily spotted with blackish, these spots usually surrounded by rufous. Back grayish brown, speckled with cinnamon and rufous. Rump and uppertail coverts dark brown, speckled with grayish white. Scapulars brown, heavily washed with cinnamon and rufous, the feathers with large, irregularly shaped blackish brown central spot. Wing coverts dark brown barred, spotted, and speckled with cinnamon and rufous; large white spot on the tip of inner two greater coverts, and sometimes a smaller white spot, edged with buff, on the tip of inner third greater covert. Primaries brown, with very small tawny spots along the outer webs of the three outermost primaries; inner primaries and secondaries dark brown, spotted with tawny. Tertials brown mottled cinnamon and rufous. Rectrices brown barred with tawny, with narrow (ca 2-3 mm wide) white tips. Lores, auriculars, and chin dark brown, speckled with cinnamon. Large white patch across the throat. Brown breast, washed or densely speckled and barred with cinnamon, with irregularly shaped blackish brown spots. Belly and flanks blackish brown, densely and narrowly barred grayish white, very sparsely spotted white. Undertail coverts blackish brown barred grayish white, and broadly tipped with white.
Juvenile: Similar to adult, but lack the white spots on the wing coverts (Robbins and Ridgely 1992); also, the markings on the upperparts and breast are more chestnut.
Very little information. Two juveniles, collected in April and June, were in heavy body molt and also were molting the flight feathers. Presumably Choco Poorwill follows the complex basic molt strategy.
Iris: dark brown (Cleere 1998) or dark gray (Holyoak 2001)
Bill: gray with black tip, blackish, or black (Cleere 1998, Holyoak 2001)
Tarsi and toes: grayish or purplish brown (Cleere 1998, Holyoak 2001)
Total length: 19.5-21 cm (Cleere 1998), 21-22.5 cm (Ridgely and Greenfield 2001b)
wing length (chord): mean 124.7 mm ± 4.2 mm (n = 8, sexes combined; Robbins and Ridgely 1992)
tail length: mean 97.2 mm ± 3.0 mm (n = 8, sexes combined; Robbins and Ridgely 1992)
bill length (from base), male: range 10.6-12.4 mm (n = ?; Cleere 1998)
bill length (from base), female): 10.3-11.2 mm (n = ?; Cleere 1998)
tarsus length, male: ca 17 mm (n = ?; Cleere 1998)
tarsus length, female: range 17.6-19.1 mm (n = ?; Cleere 1998)
Mass: 52 g (n = 1, female; Robbins and Ridgely 1992)