446

NORTHERN TROPICAL PEWEE  Contopus [cinereus] bogotensis (p. 308). Differences in voice and

plumage indicate that the bogotensis group (Mexico to n. S America) and cinereus group (e. and s. S

America; Southern Tropical Pewee) are best treated as separate species, perhaps with further cryptic

species involved.

SOUTHERN YELLOWISH FLYCATCHER  Empidonax [flavescens] flavescens (p. 312). Differences in

voice and plumage indicate that the salvini group (Mexico to Nicaragua; Northern Yellowish Flycatcher)

and flavescens group (Costa Rica to Panama) are best treated as separate species.

BLACK PHOEBE  Sayornis nigricans (p. 312). Differences in voice and plumage suggest that the nigricans

group (N America s. to Panama; Northern Black Phoebe) and latirostris group (S America; Southern

Black Phoebe) may represent separate species.

NORTHERN SOCIAL FLYCATCHER  Myiozetetes [similis] texensis (p. 316) and COLOMBIAN SOCIAL

FLYCATCHER Myiozetetes [similis] columbianus (p. 316). Differences in voice and morphology indicate

that the Social Flycatcher complex comprises at least 5 cryptic species, also including M. [s.] grandis (w.

Ecuador to nw. Peru; Western Social Flycatcher); M. [s.] similis (Amazonian region; Amazonian Social

Flycatcher); and M. [s.] pallidiventris (e. Brazil to n. Argentina; Austral Social Flycatcher).

NORTHERN STREAKED FLYCATCHER  Myiodynastes [maculatus] maculatus (p. 318). Differences in

voice and morphology indicate that the maculatus group (Mexico to S America) and solitarius group

(breeds s. S America; Austral Streaked Flycatcher) are best treated as separate species.

NUTTING’S FLYCATCHER  Myiarchus nuttingi (p. 320). Differences in plumage, morphology, and

voice between the nuttingi group (Guatemala to Costa Rica, possibly also s. Mexico; Nicoya/Ridgway’s

Flycatcher) and inquietus group (Mexico; Mexican/Godman’s Flycatcher) suggest that cryptic species may

be involved; critical study is needed.

SALVADORAN [NUTTING’S] FLYCATCHER  Myiarchus [nuttingi] flavidior (p. 320). As noted by

Howell (2012), differences in voice, morphology, and ecology indicate that the flavidior group (s. Mexico

to Nicaragua, perhaps nw. Costa Rica) is specifically distinct from nuttingi group (Mexico to Costa Rica;

Nutting’s Flycatcher, see above). Salvadoran and Nutting’s occur in parapatry (Mexico) and sympatry

(Honduras; perhaps also Mexico, Guatemala, Nicaragua), and may not even be sister species. The name

Ridgway’s Flycatcher has been suggested for flavidior (Howell 2012), but that name would be more

appropriate for nominate nuttingi if specifically distinct from inquietus, with Nutting’s Flycatcher retained

for the whole complex.

MIDDLE AMERICAN [TROPICAL] KINGBIRD  Tyrannus [melancholicus] satrapa (p. 322). Differences

in voice (especially dawn song), morphology, and plumage suggest that the satrapa group (e. Mexico to

nw. S America), occidentalis group (w. Mexico; West Mexican Kingbird), and melancholicus group (wide-

spread in S America; South American Kingbird) are best treated as separate species.

FORK-TAILED FLYCATCHER  Tyrannus savana (p. 324). Differences in morphology, ecology, and

provisionally in voice suggest that the monachus group (Mexico to nw. S America; Northern Fork-tailed

Flycatcher) and savana group (breeds s. S America; Austral Fork-tailed Flycatcher) may represent separate

species.

VIEILLOT’S [TROPICAL] MOCKINGBIRD  Mimus [gilvus] gilvus (p. 326). Differences in voice and

plumage suggest the Tropical Mockingbird complex probably comprises multiple species, including the

gracilis group (Mexico to Honduras; Mayan Mockingbird, see Howell 2019), gilvus group (Nicaragua to

n. S America and s. Caribbean, perhaps including further cryptic species), and antelius group (e. Brazil;

Brazilian Mockingbird).

WHITE-THROATED THRUSH  Turdus assimilis (p. 328). Vocal differences (most evident in call notes)

between populations e. and w. of Isthmus of Tehuantepec, Mexico, hint that cryptic species may be

involved; study needed.

SWAINSON’S THRUSH  Catharus ustulatus (p. 330). Differences in voice, plumage, and ecology suggest

that the ustulatus group (breeding w. America, wintering Mexico to n. Central America; Russet-backed

Thrush) and swainsoni group (breeding n. and interior w. N America, wintering s. Central America to S

America; Olive-backed Thrush) may represent separate species.