Sinaloa Wren

The Sinaloa wren is 11.8 to 14 cm (4.6 to 5.5 in) long and weighs 10.9 to 19.8 g (0.38 to 0.70 oz). The nominate adults have dull brown upperparts that become more rufescent on the rump. The tail is rufous brown with black or dusky bars. They have a white to buffy white supercilium, a black streak behind the eye, and dusky-striped white cheeks. The sides of the neck have broad black and white streaks. The throat and breast are white darkening to pale brown on the flanks. Juveniles are similar but their flanks are paler and more cinnamon and the facial markings less distinct. The adult T. s. cinereus is paler and grayer than the nominate. T. s. russeus' upperparts are a deep russet brown.

The Sinaloa wren is endemic to Mexico though individuals are seen almost annually in southern Arizona. T. s. cinereus is the northernmost subspecies; it is found from northeastern Sonora south to northern Sinaloa and western Chihuahua and as a visitor to Arizona. T. s. sinaloa is found from central Sinaloa and western Durango south to Michoacán. T. s. russeus is found from central Guerrero east to western Oaxaca. The species inhabits the understory of deciduous forest and its edges, both undisturbed and second growth. It also occurs in plantations.

Though no specifics have been published, the Sinaloa wren is known to be insectivorous. It forages mostly near the ground but occasionally as high as 10 m (33 ft) above it. It is assumed to capture its prey mostly by gleaning.