Ruby-crowned Kinglet
In Arizona, two species of kinglets occur: the Ruby-crowned Kinglet (Corthylio calendula) and the Golden-crowned Kinglet (Regulus satrapa). The Ruby-crowned Kinglet is widespread and common, especially in migration and winter, frequenting wooded areas, riparian corridors, and even desert vegetation during cooler months; males are distinguished by the hidden red crown patch. The Golden-crowned Kinglet is less common, primarily a winter visitor and migrant found in higher elevation coniferous forests, sometimes descending into lower woodlands in cold weather.
Among the gnatcatchers,three species are recorded in the state. The most widespread is the Blue-gray Gnatcatcher (Polioptila caerulea), common in riparian habitats, desert scrub, and oak woodlands across much of Arizona. The Black-tailed Gnatcatcher (Polioptila melanura) is characteristic of the Sonoran Desert, thriving in creosote, mesquite, and cactus habitat of the lowlands. The Black-capped Gnatcatcher (Polioptila nigriceps) is a rare but regular resident in southern Arizona, particularly in the oak and thorn scrub of the Santa Cruz and Patagonia areas, representing the northern edge of its Mexican range.