Sinaloa wren

The Sinaloa wren has three subspecies, the nominate Thryophilus sinaloa sinaloa, T. s. cinereus, and T. s. russeus.[2]

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.[3]

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.[3]

The IUCN has assessed the Sinaloa wren as being of Least Concern. Its population is estimated to exceed 500,000 individuals.[1] "Sinaloa wren can occupy scrub and second growth, and so is perhaps less vulnerable than are some other species of [the tropical deciduous forest]."[3]