Systematics

Monotypic (Ridgely and Greenfield 2001a).

The Scrub Nightjar (Caprimulgus anthonyi) is named in honor of Harold E. Anthony, formerly an Associate Curator of Mammals in the American Museum, who collected the first known specimen in an open, grassy, arid country near Portovelo, Ecuador (Chapman 1923).

The Scrub Nightjar was described as a species (Chapman 1923), but later was classified as a subspecies of Little Nightjar (Setopagis parvula) by Peters (1940) and subsequent authors, during which period this nightjar was completely unknown in life. Schwartz (1968) noted the considerable differences in plumage between parvula and anthonyi, and suggested that anthonyi was better classified as a species. This suggestion was confirmed when it was discovered that there were major differences in song between parvula and anthonyi (Robbins et al. 1994, Ridgely and Greenfield 2001a).

Phylogenetic analysis of DNA sequence data (from both mitochondrial and nuclear genes) confirms that anthonyi and parvula are distinct species. Both taxa are members of a New World radiation of nightjars, but anthonyi is the sister species to Common Pauraque (Nyctidromus albicollis), whereas parvula is near the base of a larger clade of New World nightjars (Han et al. 2011).