[5][2] Willis's antbird has three subspecies, the nominate C. l. laeta (Todd, 1920), C. l. waimiri (Bierregaard, Cohn-Haft & Stotz, 1997), and C. l. sabinoi (Pinto, 1939).

Males of subspecies C. l. waimiri are a darker gray than the nominate and do not have white tips on the tail feathers.

It is found in north-central Amazonian Brazil where eastern Roraima, northeastern Amazonas, and northwestern Pará meet and also into southern Guyana.

The nominate subspecies is found in southeastern Amazonian Brazil, in eastern Pará and western Maranhão.

Subspecies C. l. waimiri favors campina woodlands on white sand soil, especially along streams and in swampy areas.

It seldom joins mixed-species feeding flocks, and occasionally attends army ant swarms but spends little time with them.

[6] The breeding season of Willis's antbird includes February and March in Pará but is otherwise unknown.

The song of the male Willis's antbird is a "very high, short, very sharp 'puh-wéedi-wéedi-wéedih'"; the "wéedi" is repeated two to five times.

"The ability of all races to exploit second-growth and edge habitats probably renders this species less vulnerable to disturbance than are most antbirds.