The Sonora Sucker (Gila Sucker), Catostomus insignis, is a medium-sized catostomid fish with 16 other species in the genus scattered throughout North America. This species is remarkably similar in appearance to the Yaqui Sucker (C. bernardini). Sonora suckers have a fusiform body, with large heads and chubby figures. They have generally large lower lips, with no fleshy lobes. Sonora suckers have unique square dorsal fins, and relatively large scales (but fewer than most fish in the genus Catostomus). Their coloration is distinctly bi-colored, with a yellow underside and brownish dorsal side. Each scale has discrete outlines to form a definite spot. Adults can reach a length of 80 cm (31.5 in), and can weigh to about 2 kg (4.4 lbs). The Sonora sucker occurs mainly in New Mexico and Arizona, also in northern Sonora, Mexico. This species is most prevalent in the Gila and Bill Williams river basins in Arizona, and common in the Gila and San Francisco drainages in New Mexico. Habitat The Sonora sucker can live in an array of habitats, varying from trout streams to warm water rivers. However, these fish prefer rocky, relatively deep, and quiet waters.[5] During daylight, adult Sonora suckers tend to take cover and stay in the shade.
