Nightjars are long winged, short legged crepuscular or nocturnal birds with predominantly brown cryptic plumage, conspicuous rictal bristles, and short bills with a very wide gape. Nighthawks (Chordeiles) are nightjars with long, pointed wings and a relatively long tail. The plumage of Sand-colored Nighthawk is intricately patterned with white and brown. The underparts are mostly plain white and gray, with the upperparts primarily patterned light gray and brown. There is a broad white stripe across the base of the secondaries and primaries on the upper surface of the wing, and the under surface of the wing also is mostly white. The sides of the tail also are extensively white. The sexes are similar, but females have more mottling on the breast, and have a brown tip to the tail (the tail tip is black in males).
Sand-colored Nighthawk is unlikely to be confused with any other species, especially in flight, when the bold wing pattern and white underparts are visible. At rest, compare to Nacunda Nighthawk (Chordeiles nacunda) and to Ladder-tailed Nightjar (Hydropsalis climacocerca). Sand-colored Nighthawk is the only species of nightjar, however, then regularly roosts in large aggregations on open sandbars. At a great distance, conceivably could be confused in flight with Yellow-billed Tern (Sternula superciliaris) (Sick 1950, 1993).
The following description is based on Cleere (1998) and on Schulenberg et al. (2010), and refers to nominate rupestris; see also Geographic Variation:
Adult male: Forecrown, crown, and nape pale grayish brown, tinged with cinnamon, and heavily spotted with blackish brown; sides of the crown above the eyes whiter or buffier. Back, rump, and uppertail coverts pale grayish brown, streaked, barred, and star-spotted with brown. Tail extensively white. The four outermost pairs of rectrices (R5-R2) mostly white but with broad (ca 20 mm) black tips; the outer web of R5 also brown. The central pair of rectrices (R1) pale grayish brown, narrowly barred with brown, and ca 22 shorter than the outermost pair, producing a notch at the tip of the tail. Wing coverts and scapulars pale grayish brown, washed with white and cinnamon, and star-spotted with blackish brown. Outer primaries (P10-P7) brown; inner primaries (P6-P1) mostly white, tipped with brown. Secondaries mostly white, tipped with brown. Tertials pale grayish brown tinged with cinnamon, barred and streaked with brown, and tipped with white. Lores and auriculars cinnamon. Chin and throat white or buffy white. Breast grayish white, tinged with cinnamon, and barred and spotted with brown. Upper belly white with gorget of brown spots. Lower belly and flanks white, often tinged with buffy. Undertail coverts white. Underwing coverts white.
Adult female: Similar to adult male, but tips of rectrices brown (not black), and with more extensive mottling on the breast.
Juvenile and immature: Similar to adult, but perhaps paler.
Very little information. Friedmann (1948) noted wing molt in several specimens collected in Venezuela in January.
Iris: dark brown
Bill: black, grayish brown
Tarsi and toes: brown, grayish brown
Bare parts color data from Cleere (1998) and from specimens in the Field Museum of Natural History.
Total length: 20.5-21.5 cm (Ridgely and Greenfield 2001b), 22 cm (Hilty and Brown 1986)
Linear measurements (from Oberholser 1914):
male (n = 3)
wing length: range 167-172.5 mm
tail length: range 94-100 mm
bill length (exposed culmen): range 6.5-7.0 mm
tarsus length: range 12-13.5 mm
female (n = 3)
wing length: range 159.5-165.5 mm
tail length: range 89-92.5 mm
bill length (exposed culmen): range 5.0-7.5 mm
tarsus length: range 12-13.5 mm
Mass: No data. A report of a mass of 20 g (Leite et al. 2007) clearly is in error.